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style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/1995/">1995</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/1996/">1996</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/1997/">1997</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/1998/">1998</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/1999/">1999</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/2000/">2000</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/2001/">2001</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/2002/">2002</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/2003/">2003</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/2004/">2004</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/2005/">2005</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/2006/">2006</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/2007/">2007</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/2008/">2008</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/2009/">2009</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/2010/">2010</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/2011/">2011</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/2012/">2012</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/2013/">2013</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/2014/">2014</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/2015/">2015</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/2016/">2016</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/2017/">2017</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/2018/">2018</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/2019/">2019</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/2020/">2020</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/2021/">2021</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/2022/">2022</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/2023/">2023</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/2024/">2024</a><a class="date-selector" style="cursor:pointer;border:none;color:var(--color-black);border-radius:0.5rem;padding:0.25rem 0.5rem;font-weight:400;text-decoration:none" href="/archive/issues/2025/">2025</a></div></div></div><div class="issue__list-8JHD2"><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/supplements/1919/12-27/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/491908EE-28E1-4246-84DECCB1382A5C9F_source.gif?w=600" alt="SA Supplements Vol 88 Issue 2292supp" srcSet="https://static.scientificamerican.com/sciam/cache/file/491908EE-28E1-4246-84DECCB1382A5C9F_source.gif?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/491908EE-28E1-4246-84DECCB1382A5C9F_source.gif?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Supplements</h3><div class="issue__date-ozuG1"><time dateTime="1919-12-27">December 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/sa/1919/12-27/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/5CB37290-DCC7-42AF-BE8204BD42BCB8BC_source.jpg?w=600" alt="Scientific American Magazine Vol 121 Issue 26" srcSet="https://static.scientificamerican.com/sciam/cache/file/5CB37290-DCC7-42AF-BE8204BD42BCB8BC_source.jpg?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/5CB37290-DCC7-42AF-BE8204BD42BCB8BC_source.jpg?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Scientific American</h3><div class="issue__date-ozuG1"><time dateTime="1919-12-27">December 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/supplements/1919/12-20/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/88EA798B-0138-48A9-83BEF1CF875538A1_source.gif?w=600" alt="SA Supplements Vol 88 Issue 2291supp" srcSet="https://static.scientificamerican.com/sciam/cache/file/88EA798B-0138-48A9-83BEF1CF875538A1_source.gif?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/88EA798B-0138-48A9-83BEF1CF875538A1_source.gif?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Supplements</h3><div class="issue__date-ozuG1"><time dateTime="1919-12-20">December 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/sa/1919/12-20/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/B0693930-5477-45A6-99D8E8816ECBE775_source.jpg?w=600" alt="Scientific American Magazine Vol 121 Issue 25" srcSet="https://static.scientificamerican.com/sciam/cache/file/B0693930-5477-45A6-99D8E8816ECBE775_source.jpg?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/B0693930-5477-45A6-99D8E8816ECBE775_source.jpg?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Scientific American</h3><div class="issue__date-ozuG1"><time dateTime="1919-12-20">December 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/supplements/1919/12-13/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/57179A91-43F3-41A1-86816692B4731547_source.gif?w=600" alt="SA Supplements Vol 88 Issue 2290supp" srcSet="https://static.scientificamerican.com/sciam/cache/file/57179A91-43F3-41A1-86816692B4731547_source.gif?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/57179A91-43F3-41A1-86816692B4731547_source.gif?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Supplements</h3><div class="issue__date-ozuG1"><time dateTime="1919-12-13">December 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/sa/1919/12-13/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/B6C15837-5FA1-4F0D-B8922B7BAA91C96E_source.jpg?w=600" alt="Scientific American Magazine Vol 121 Issue 24" srcSet="https://static.scientificamerican.com/sciam/cache/file/B6C15837-5FA1-4F0D-B8922B7BAA91C96E_source.jpg?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/B6C15837-5FA1-4F0D-B8922B7BAA91C96E_source.jpg?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Scientific American</h3><div class="issue__date-ozuG1"><time dateTime="1919-12-13">December 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/supplements/1919/12-06/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/912C6822-91DA-4828-9F59739AEFFBD5C6_source.gif?w=600" alt="SA Supplements Vol 88 Issue 2289supp" srcSet="https://static.scientificamerican.com/sciam/cache/file/912C6822-91DA-4828-9F59739AEFFBD5C6_source.gif?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/912C6822-91DA-4828-9F59739AEFFBD5C6_source.gif?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Supplements</h3><div class="issue__date-ozuG1"><time dateTime="1919-12-06">December 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/sa/1919/12-06/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/BA0727CF-F6AA-45E2-9422085F700A4550_source.jpg?w=600" alt="Scientific American Magazine Vol 121 Issue 23" srcSet="https://static.scientificamerican.com/sciam/cache/file/BA0727CF-F6AA-45E2-9422085F700A4550_source.jpg?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/BA0727CF-F6AA-45E2-9422085F700A4550_source.jpg?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Scientific American</h3><div class="issue__date-ozuG1"><time dateTime="1919-12-06">December 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/sa/1919/11-29/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/BD41BD66-472C-4116-B56AF0631D351E16_source.jpg?w=600" alt="Scientific American Magazine Vol 121 Issue 22" srcSet="https://static.scientificamerican.com/sciam/cache/file/BD41BD66-472C-4116-B56AF0631D351E16_source.jpg?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/BD41BD66-472C-4116-B56AF0631D351E16_source.jpg?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Scientific American</h3><div class="issue__date-ozuG1"><time dateTime="1919-11-29">November 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/supplements/1919/11-29/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/66D020A7-5D37-48E8-9835A986736CF4D3_source.gif?w=600" alt="SA Supplements Vol 88 Issue 2288supp" srcSet="https://static.scientificamerican.com/sciam/cache/file/66D020A7-5D37-48E8-9835A986736CF4D3_source.gif?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/66D020A7-5D37-48E8-9835A986736CF4D3_source.gif?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Supplements</h3><div class="issue__date-ozuG1"><time dateTime="1919-11-29">November 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/supplements/1919/11-22/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/FB4063F4-69BD-4F09-9178DC3243B00358_source.gif?w=600" alt="SA Supplements Vol 88 Issue 2287supp" srcSet="https://static.scientificamerican.com/sciam/cache/file/FB4063F4-69BD-4F09-9178DC3243B00358_source.gif?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/FB4063F4-69BD-4F09-9178DC3243B00358_source.gif?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Supplements</h3><div class="issue__date-ozuG1"><time dateTime="1919-11-22">November 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/sa/1919/11-22/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/D5892FC5-CFF9-40D5-B02E6FFBC6729C6D_source.jpg?w=600" alt="Scientific American Magazine Vol 121 Issue 21" srcSet="https://static.scientificamerican.com/sciam/cache/file/D5892FC5-CFF9-40D5-B02E6FFBC6729C6D_source.jpg?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/D5892FC5-CFF9-40D5-B02E6FFBC6729C6D_source.jpg?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Scientific American</h3><div class="issue__date-ozuG1"><time dateTime="1919-11-22">November 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/supplements/1919/11-15/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/A3729E3C-F59D-4B90-A6998ABAD5B2D1A7_source.gif?w=600" alt="SA Supplements Vol 88 Issue 2286supp" srcSet="https://static.scientificamerican.com/sciam/cache/file/A3729E3C-F59D-4B90-A6998ABAD5B2D1A7_source.gif?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/A3729E3C-F59D-4B90-A6998ABAD5B2D1A7_source.gif?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Supplements</h3><div class="issue__date-ozuG1"><time dateTime="1919-11-15">November 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/sa/1919/11-15/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/B705FEB6-88C6-4DB2-B2E3442C1B89B830_source.jpg?w=600" alt="Scientific American Magazine Vol 121 Issue 20" srcSet="https://static.scientificamerican.com/sciam/cache/file/B705FEB6-88C6-4DB2-B2E3442C1B89B830_source.jpg?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/B705FEB6-88C6-4DB2-B2E3442C1B89B830_source.jpg?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Scientific American</h3><div class="issue__date-ozuG1"><time dateTime="1919-11-15">November 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/supplements/1919/11-08/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/DEECFB46-3F0F-4F90-807561A327F52219_source.gif?w=600" alt="SA Supplements Vol 88 Issue 2285supp" srcSet="https://static.scientificamerican.com/sciam/cache/file/DEECFB46-3F0F-4F90-807561A327F52219_source.gif?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/DEECFB46-3F0F-4F90-807561A327F52219_source.gif?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Supplements</h3><div class="issue__date-ozuG1"><time dateTime="1919-11-08">November 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/sa/1919/11-08/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/9B28D259-1848-400D-A77F22D3F6725971_source.jpg?w=600" alt="Scientific American Magazine Vol 121 Issue 19" srcSet="https://static.scientificamerican.com/sciam/cache/file/9B28D259-1848-400D-A77F22D3F6725971_source.jpg?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/9B28D259-1848-400D-A77F22D3F6725971_source.jpg?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Scientific American</h3><div class="issue__date-ozuG1"><time dateTime="1919-11-08">November 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/sa/1919/11-01/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/72810E5A-C8B4-4ECD-BE8CE41AA5D1927A_source.jpg?w=600" alt="Scientific American Magazine Vol 121 Issue 18" srcSet="https://static.scientificamerican.com/sciam/cache/file/72810E5A-C8B4-4ECD-BE8CE41AA5D1927A_source.jpg?w=300 300w, 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width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Supplements</h3><div class="issue__date-ozuG1"><time dateTime="1919-10-25">October 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/sa/1919/10-25/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/8C9299B7-89C8-4101-8D5558D9E1716400_source.jpg?w=600" alt="Scientific American Magazine Vol 121 Issue 17" srcSet="https://static.scientificamerican.com/sciam/cache/file/8C9299B7-89C8-4101-8D5558D9E1716400_source.jpg?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/8C9299B7-89C8-4101-8D5558D9E1716400_source.jpg?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Scientific American</h3><div class="issue__date-ozuG1"><time dateTime="1919-10-25">October 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/sa/1919/10-18/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/6C705601-68EC-45CD-AD53732ED7ADB5E8_source.jpg?w=600" alt="Scientific American Magazine Vol 121 Issue 16" srcSet="https://static.scientificamerican.com/sciam/cache/file/6C705601-68EC-45CD-AD53732ED7ADB5E8_source.jpg?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/6C705601-68EC-45CD-AD53732ED7ADB5E8_source.jpg?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Scientific American</h3><div class="issue__date-ozuG1"><time dateTime="1919-10-18">October 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/supplements/1919/10-11/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/77D036DB-F0FA-4912-94CAE2D5EB902746_source.gif?w=600" alt="SA Supplements Vol 88 Issue 2283supp" srcSet="https://static.scientificamerican.com/sciam/cache/file/77D036DB-F0FA-4912-94CAE2D5EB902746_source.gif?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/77D036DB-F0FA-4912-94CAE2D5EB902746_source.gif?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Supplements</h3><div class="issue__date-ozuG1"><time dateTime="1919-10-11">October 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/sa/1919/10-11/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/A8AAD4E6-5C0B-4C98-B5073BC15BEE6930_source.jpg?w=600" alt="Scientific American Magazine Vol 121 Issue 15" srcSet="https://static.scientificamerican.com/sciam/cache/file/A8AAD4E6-5C0B-4C98-B5073BC15BEE6930_source.jpg?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/A8AAD4E6-5C0B-4C98-B5073BC15BEE6930_source.jpg?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Scientific American</h3><div class="issue__date-ozuG1"><time dateTime="1919-10-11">October 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/sa/1919/10-04/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/AF56ABF2-4867-4175-A9F26B418F8A09D0_source.jpg?w=600" alt="Scientific American Magazine Vol 121 Issue 14" srcSet="https://static.scientificamerican.com/sciam/cache/file/AF56ABF2-4867-4175-A9F26B418F8A09D0_source.jpg?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/AF56ABF2-4867-4175-A9F26B418F8A09D0_source.jpg?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Scientific American</h3><div class="issue__date-ozuG1"><time dateTime="1919-10-04">October 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/supplements/1919/09-27/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/893507CB-E9A0-4D12-B97A2650CE72A053_source.gif?w=600" alt="SA Supplements Vol 88 Issue 2282supp" srcSet="https://static.scientificamerican.com/sciam/cache/file/893507CB-E9A0-4D12-B97A2650CE72A053_source.gif?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/893507CB-E9A0-4D12-B97A2650CE72A053_source.gif?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Supplements</h3><div class="issue__date-ozuG1"><time dateTime="1919-09-27">September 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/sa/1919/09-27/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/38433BB6-2FDB-45AB-8B43A6015CFAFFE6_source.jpg?w=600" alt="Scientific American Magazine Vol 121 Issue 13" srcSet="https://static.scientificamerican.com/sciam/cache/file/38433BB6-2FDB-45AB-8B43A6015CFAFFE6_source.jpg?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/38433BB6-2FDB-45AB-8B43A6015CFAFFE6_source.jpg?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Scientific American</h3><div class="issue__date-ozuG1"><time dateTime="1919-09-27">September 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/supplements/1919/09-20/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/CA9DD6E0-5C03-459C-BFD80F2B8905E790_source.gif?w=600" alt="SA Supplements Vol 88 Issue 2281supp" srcSet="https://static.scientificamerican.com/sciam/cache/file/CA9DD6E0-5C03-459C-BFD80F2B8905E790_source.gif?w=300 300w, 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loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Scientific American</h3><div class="issue__date-ozuG1"><time dateTime="1919-09-20">September 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/supplements/1919/09-13/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/BA50B824-C38E-4044-B5585BD5B6AE0805_source.gif?w=600" alt="SA Supplements Vol 88 Issue 2280supp" srcSet="https://static.scientificamerican.com/sciam/cache/file/BA50B824-C38E-4044-B5585BD5B6AE0805_source.gif?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/BA50B824-C38E-4044-B5585BD5B6AE0805_source.gif?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Supplements</h3><div class="issue__date-ozuG1"><time dateTime="1919-09-13">September 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/sa/1919/09-13/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/BBA96C97-23E4-4FDC-AA1A8F42E5D850CF_source.jpg?w=600" alt="Scientific American Magazine Vol 121 Issue 11" srcSet="https://static.scientificamerican.com/sciam/cache/file/BBA96C97-23E4-4FDC-AA1A8F42E5D850CF_source.jpg?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/BBA96C97-23E4-4FDC-AA1A8F42E5D850CF_source.jpg?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Scientific American</h3><div class="issue__date-ozuG1"><time dateTime="1919-09-13">September 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/supplements/1919/09-06/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/AF19EF8E-F1F4-40E7-AE1704F1D1229841_source.gif?w=600" alt="SA Supplements Vol 88 Issue 2279supp" srcSet="https://static.scientificamerican.com/sciam/cache/file/AF19EF8E-F1F4-40E7-AE1704F1D1229841_source.gif?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/AF19EF8E-F1F4-40E7-AE1704F1D1229841_source.gif?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Supplements</h3><div class="issue__date-ozuG1"><time dateTime="1919-09-06">September 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/sa/1919/09-06/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/D397BE4C-7FC1-42CD-AA1ED1A4D58995E5_source.jpg?w=600" alt="Scientific American Magazine Vol 121 Issue 10" srcSet="https://static.scientificamerican.com/sciam/cache/file/D397BE4C-7FC1-42CD-AA1ED1A4D58995E5_source.jpg?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/D397BE4C-7FC1-42CD-AA1ED1A4D58995E5_source.jpg?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Scientific American</h3><div class="issue__date-ozuG1"><time dateTime="1919-09-06">September 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/supplements/1919/08-30/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/757E1632-4A31-447B-B1772DA0642BB352_source.gif?w=600" alt="SA Supplements Vol 88 Issue 2278supp" srcSet="https://static.scientificamerican.com/sciam/cache/file/757E1632-4A31-447B-B1772DA0642BB352_source.gif?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/757E1632-4A31-447B-B1772DA0642BB352_source.gif?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Supplements</h3><div class="issue__date-ozuG1"><time dateTime="1919-08-30">August 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/sa/1919/08-30/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/B3322414-A12F-4F01-973723ADADA5C8C7_source.jpg?w=600" alt="Scientific American Magazine Vol 121 Issue 9" srcSet="https://static.scientificamerican.com/sciam/cache/file/B3322414-A12F-4F01-973723ADADA5C8C7_source.jpg?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/B3322414-A12F-4F01-973723ADADA5C8C7_source.jpg?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Scientific American</h3><div class="issue__date-ozuG1"><time dateTime="1919-08-30">August 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/supplements/1919/08-23/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/3310B97E-0489-4A75-AE2E27501B70E207_source.gif?w=600" alt="SA Supplements Vol 88 Issue 2277supp" srcSet="https://static.scientificamerican.com/sciam/cache/file/3310B97E-0489-4A75-AE2E27501B70E207_source.gif?w=300 300w, 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loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Scientific American</h3><div class="issue__date-ozuG1"><time dateTime="1919-08-23">August 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/supplements/1919/08-16/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/D6FD7DAB-7B8B-4C7D-8C0E3818074A4B4F_source.gif?w=600" alt="SA Supplements Vol 88 Issue 2276supp" srcSet="https://static.scientificamerican.com/sciam/cache/file/D6FD7DAB-7B8B-4C7D-8C0E3818074A4B4F_source.gif?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/D6FD7DAB-7B8B-4C7D-8C0E3818074A4B4F_source.gif?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Supplements</h3><div class="issue__date-ozuG1"><time dateTime="1919-08-16">August 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/sa/1919/08-16/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/AFF6FE4C-EE9C-434B-89AF32661E6ED536_source.jpg?w=600" alt="Scientific American Magazine Vol 121 Issue 7" srcSet="https://static.scientificamerican.com/sciam/cache/file/AFF6FE4C-EE9C-434B-89AF32661E6ED536_source.jpg?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/AFF6FE4C-EE9C-434B-89AF32661E6ED536_source.jpg?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Scientific American</h3><div class="issue__date-ozuG1"><time dateTime="1919-08-16">August 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/supplements/1919/08-09/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/C479FDEE-B9EC-496E-BF1D4E8D288EC50F_source.gif?w=600" alt="SA Supplements Vol 88 Issue 2275supp" srcSet="https://static.scientificamerican.com/sciam/cache/file/C479FDEE-B9EC-496E-BF1D4E8D288EC50F_source.gif?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/C479FDEE-B9EC-496E-BF1D4E8D288EC50F_source.gif?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Supplements</h3><div class="issue__date-ozuG1"><time dateTime="1919-08-09">August 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/sa/1919/08-09/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/CF77D86A-8689-4A3A-A4AD0F7728374FE3_source.jpg?w=600" alt="Scientific American Magazine Vol 121 Issue 6" srcSet="https://static.scientificamerican.com/sciam/cache/file/CF77D86A-8689-4A3A-A4AD0F7728374FE3_source.jpg?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/CF77D86A-8689-4A3A-A4AD0F7728374FE3_source.jpg?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Scientific American</h3><div class="issue__date-ozuG1"><time dateTime="1919-08-09">August 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/supplements/1919/08-02/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/F4DDF09F-1FA1-4A04-8D2306D8A27C418E_source.gif?w=600" alt="SA Supplements Vol 88 Issue 2274supp" srcSet="https://static.scientificamerican.com/sciam/cache/file/F4DDF09F-1FA1-4A04-8D2306D8A27C418E_source.gif?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/F4DDF09F-1FA1-4A04-8D2306D8A27C418E_source.gif?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Supplements</h3><div class="issue__date-ozuG1"><time dateTime="1919-08-02">August 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/sa/1919/08-02/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/797D308A-8B7C-4923-BDBCB0E28C8C03F5_source.jpg?w=600" alt="Scientific American Magazine Vol 121 Issue 5" srcSet="https://static.scientificamerican.com/sciam/cache/file/797D308A-8B7C-4923-BDBCB0E28C8C03F5_source.jpg?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/797D308A-8B7C-4923-BDBCB0E28C8C03F5_source.jpg?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Scientific American</h3><div class="issue__date-ozuG1"><time dateTime="1919-08-02">August 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/supplements/1919/07-26/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/584F3BB6-9171-4277-AC02240FA650C7E0_source.gif?w=600" alt="SA Supplements Vol 88 Issue 2273supp" srcSet="https://static.scientificamerican.com/sciam/cache/file/584F3BB6-9171-4277-AC02240FA650C7E0_source.gif?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/584F3BB6-9171-4277-AC02240FA650C7E0_source.gif?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Supplements</h3><div class="issue__date-ozuG1"><time dateTime="1919-07-26">July 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/sa/1919/07-26/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/7B5D612E-4071-4E6F-95561EC7066C3596_source.jpg?w=600" alt="Scientific American Magazine Vol 121 Issue 4" srcSet="https://static.scientificamerican.com/sciam/cache/file/7B5D612E-4071-4E6F-95561EC7066C3596_source.jpg?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/7B5D612E-4071-4E6F-95561EC7066C3596_source.jpg?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Scientific American</h3><div class="issue__date-ozuG1"><time dateTime="1919-07-26">July 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/supplements/1919/07-19/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/6440BB09-EBFD-42DB-8D9AB562AC95CBCC_source.gif?w=600" alt="SA Supplements Vol 88 Issue 2272supp" srcSet="https://static.scientificamerican.com/sciam/cache/file/6440BB09-EBFD-42DB-8D9AB562AC95CBCC_source.gif?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/6440BB09-EBFD-42DB-8D9AB562AC95CBCC_source.gif?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Supplements</h3><div class="issue__date-ozuG1"><time dateTime="1919-07-19">July 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/sa/1919/07-19/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/1DE4ADEA-E19E-44CB-8BAB06E1BE6350E4_source.jpg?w=600" alt="Scientific American Magazine Vol 121 Issue 3" srcSet="https://static.scientificamerican.com/sciam/cache/file/1DE4ADEA-E19E-44CB-8BAB06E1BE6350E4_source.jpg?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/1DE4ADEA-E19E-44CB-8BAB06E1BE6350E4_source.jpg?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Scientific American</h3><div class="issue__date-ozuG1"><time dateTime="1919-07-19">July 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/supplements/1919/07-12/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/FE1F562A-D35C-467F-A12E8191B9EE9511_source.gif?w=600" alt="SA Supplements Vol 88 Issue 2271supp" srcSet="https://static.scientificamerican.com/sciam/cache/file/FE1F562A-D35C-467F-A12E8191B9EE9511_source.gif?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/FE1F562A-D35C-467F-A12E8191B9EE9511_source.gif?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Supplements</h3><div class="issue__date-ozuG1"><time dateTime="1919-07-12">July 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/sa/1919/07-12/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/FF7E1CF6-6C4B-48DE-B72A1A468DBCFCB2_source.jpg?w=600" alt="Scientific American Magazine Vol 121 Issue 2" srcSet="https://static.scientificamerican.com/sciam/cache/file/FF7E1CF6-6C4B-48DE-B72A1A468DBCFCB2_source.jpg?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/FF7E1CF6-6C4B-48DE-B72A1A468DBCFCB2_source.jpg?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Scientific American</h3><div class="issue__date-ozuG1"><time dateTime="1919-07-12">July 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/supplements/1919/07-05/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/391D6E49-64A5-4942-9454751F0F17ED49_source.gif?w=600" alt="SA Supplements Vol 88 Issue 2270supp" srcSet="https://static.scientificamerican.com/sciam/cache/file/391D6E49-64A5-4942-9454751F0F17ED49_source.gif?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/391D6E49-64A5-4942-9454751F0F17ED49_source.gif?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Supplements</h3><div class="issue__date-ozuG1"><time dateTime="1919-07-05">July 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/sa/1919/07-05/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/D912473E-AF91-48D3-9BB44FB069E5CC4D_source.jpg?w=600" alt="Scientific American Magazine Vol 121 Issue 1" srcSet="https://static.scientificamerican.com/sciam/cache/file/D912473E-AF91-48D3-9BB44FB069E5CC4D_source.jpg?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/D912473E-AF91-48D3-9BB44FB069E5CC4D_source.jpg?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Scientific American</h3><div class="issue__date-ozuG1"><time dateTime="1919-07-05">July 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/supplements/1919/06-28/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/A42C459E-854B-45CC-B4E1EBEB8B22649B_source.gif?w=600" alt="SA Supplements Vol 87 Issue 2269supp" srcSet="https://static.scientificamerican.com/sciam/cache/file/A42C459E-854B-45CC-B4E1EBEB8B22649B_source.gif?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/A42C459E-854B-45CC-B4E1EBEB8B22649B_source.gif?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Supplements</h3><div class="issue__date-ozuG1"><time dateTime="1919-06-28">June 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/sa/1919/06-28/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/BBAF9E9E-D016-4811-92C1854C7AB33066_source.jpg?w=600" alt="Scientific American Magazine Vol 120 Issue 26" srcSet="https://static.scientificamerican.com/sciam/cache/file/BBAF9E9E-D016-4811-92C1854C7AB33066_source.jpg?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/BBAF9E9E-D016-4811-92C1854C7AB33066_source.jpg?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Scientific American</h3><div class="issue__date-ozuG1"><time dateTime="1919-06-28">June 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/supplements/1919/06-21/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/5054D0FA-3BAC-4598-A5D68503CF80CBCE_source.gif?w=600" alt="SA Supplements Vol 87 Issue 2268supp" srcSet="https://static.scientificamerican.com/sciam/cache/file/5054D0FA-3BAC-4598-A5D68503CF80CBCE_source.gif?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/5054D0FA-3BAC-4598-A5D68503CF80CBCE_source.gif?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Supplements</h3><div class="issue__date-ozuG1"><time dateTime="1919-06-21">June 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/sa/1919/06-21/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/214A4A61-461F-4592-B3D903E6282D130A_source.jpg?w=600" alt="Scientific American Magazine Vol 120 Issue 25" srcSet="https://static.scientificamerican.com/sciam/cache/file/214A4A61-461F-4592-B3D903E6282D130A_source.jpg?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/214A4A61-461F-4592-B3D903E6282D130A_source.jpg?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Scientific American</h3><div class="issue__date-ozuG1"><time dateTime="1919-06-21">June 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/supplements/1919/06-14/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/007A28D5-6FDC-421C-9D910FE0CA67A9D0_source.gif?w=600" alt="SA Supplements Vol 87 Issue 2267supp" srcSet="https://static.scientificamerican.com/sciam/cache/file/007A28D5-6FDC-421C-9D910FE0CA67A9D0_source.gif?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/007A28D5-6FDC-421C-9D910FE0CA67A9D0_source.gif?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Supplements</h3><div class="issue__date-ozuG1"><time dateTime="1919-06-14">June 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/sa/1919/06-14/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/5FE7B3F5-8E1F-4AE6-B968376CADB2E607_source.jpg?w=600" alt="Scientific American Magazine Vol 120 Issue 24" srcSet="https://static.scientificamerican.com/sciam/cache/file/5FE7B3F5-8E1F-4AE6-B968376CADB2E607_source.jpg?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/5FE7B3F5-8E1F-4AE6-B968376CADB2E607_source.jpg?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Scientific American</h3><div class="issue__date-ozuG1"><time dateTime="1919-06-14">June 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/supplements/1919/06-07/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/B72E1F9D-8EB0-4114-9FE6D87A68D506BE_source.gif?w=600" alt="SA Supplements Vol 87 Issue 2266supp" srcSet="https://static.scientificamerican.com/sciam/cache/file/B72E1F9D-8EB0-4114-9FE6D87A68D506BE_source.gif?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/B72E1F9D-8EB0-4114-9FE6D87A68D506BE_source.gif?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Supplements</h3><div class="issue__date-ozuG1"><time dateTime="1919-06-07">June 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/sa/1919/06-07/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/C8365673-32F9-474F-8E6B668496B638DA_source.jpg?w=600" alt="Scientific American Magazine Vol 120 Issue 23" srcSet="https://static.scientificamerican.com/sciam/cache/file/C8365673-32F9-474F-8E6B668496B638DA_source.jpg?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/C8365673-32F9-474F-8E6B668496B638DA_source.jpg?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Scientific American</h3><div class="issue__date-ozuG1"><time dateTime="1919-06-07">June 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/sa/1919/05-31/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/6DDD96BB-0276-4870-A07B66DEE4B68C19_source.jpg?w=600" alt="Scientific American Magazine Vol 120 Issue 22" srcSet="https://static.scientificamerican.com/sciam/cache/file/6DDD96BB-0276-4870-A07B66DEE4B68C19_source.jpg?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/6DDD96BB-0276-4870-A07B66DEE4B68C19_source.jpg?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Scientific American</h3><div class="issue__date-ozuG1"><time dateTime="1919-05-31">May 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/supplements/1919/05-31/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/F1FADD86-990A-4F1D-8489E03BEE57D3F6_source.gif?w=600" alt="SA Supplements Vol 87 Issue 2265supp" srcSet="https://static.scientificamerican.com/sciam/cache/file/F1FADD86-990A-4F1D-8489E03BEE57D3F6_source.gif?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/F1FADD86-990A-4F1D-8489E03BEE57D3F6_source.gif?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Supplements</h3><div class="issue__date-ozuG1"><time dateTime="1919-05-31">May 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/supplements/1919/05-24/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/7EC68BDE-C591-4813-97573FCBDECFFED2_source.gif?w=600" alt="SA Supplements Vol 87 Issue 2264supp" srcSet="https://static.scientificamerican.com/sciam/cache/file/7EC68BDE-C591-4813-97573FCBDECFFED2_source.gif?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/7EC68BDE-C591-4813-97573FCBDECFFED2_source.gif?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Supplements</h3><div class="issue__date-ozuG1"><time dateTime="1919-05-24">May 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/sa/1919/05-24/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/0969A820-40E2-4A84-BB1AA7AB77803EDF_source.jpg?w=600" alt="Scientific American Magazine Vol 120 Issue 21" srcSet="https://static.scientificamerican.com/sciam/cache/file/0969A820-40E2-4A84-BB1AA7AB77803EDF_source.jpg?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/0969A820-40E2-4A84-BB1AA7AB77803EDF_source.jpg?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Scientific American</h3><div class="issue__date-ozuG1"><time dateTime="1919-05-24">May 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/supplements/1919/05-17/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/3F2CAC66-AD47-4592-B51BB5DA66CA37E0_source.gif?w=600" alt="SA Supplements Vol 87 Issue 2263supp" srcSet="https://static.scientificamerican.com/sciam/cache/file/3F2CAC66-AD47-4592-B51BB5DA66CA37E0_source.gif?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/3F2CAC66-AD47-4592-B51BB5DA66CA37E0_source.gif?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Supplements</h3><div class="issue__date-ozuG1"><time dateTime="1919-05-17">May 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/sa/1919/05-17/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/83C29DAF-51BE-43FE-94A01706618ED9CD_source.jpg?w=600" alt="Scientific American Magazine Vol 120 Issue 20" srcSet="https://static.scientificamerican.com/sciam/cache/file/83C29DAF-51BE-43FE-94A01706618ED9CD_source.jpg?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/83C29DAF-51BE-43FE-94A01706618ED9CD_source.jpg?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Scientific American</h3><div class="issue__date-ozuG1"><time dateTime="1919-05-17">May 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/supplements/1919/05-10/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/08127A76-E0BA-401D-915D7861EB665DEC_source.gif?w=600" alt="SA Supplements Vol 87 Issue 2262supp" srcSet="https://static.scientificamerican.com/sciam/cache/file/08127A76-E0BA-401D-915D7861EB665DEC_source.gif?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/08127A76-E0BA-401D-915D7861EB665DEC_source.gif?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Supplements</h3><div class="issue__date-ozuG1"><time dateTime="1919-05-10">May 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/sa/1919/05-10/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/0E78C9C2-B32C-4D28-AFA41C63F10B2781_source.jpg?w=600" alt="Scientific American Magazine Vol 120 Issue 19" srcSet="https://static.scientificamerican.com/sciam/cache/file/0E78C9C2-B32C-4D28-AFA41C63F10B2781_source.jpg?w=300 300w, 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loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Supplements</h3><div class="issue__date-ozuG1"><time dateTime="1919-05-03">May 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/sa/1919/05-03/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/4957AF73-FD26-4704-AB8473619AD3C6F0_source.jpg?w=600" alt="Scientific American Magazine Vol 120 Issue 18" srcSet="https://static.scientificamerican.com/sciam/cache/file/4957AF73-FD26-4704-AB8473619AD3C6F0_source.jpg?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/4957AF73-FD26-4704-AB8473619AD3C6F0_source.jpg?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Scientific American</h3><div class="issue__date-ozuG1"><time dateTime="1919-05-03">May 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/supplements/1919/04-26/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/D9E45E6A-C03B-4B06-856D5FDAFDB341A9_source.gif?w=600" alt="SA Supplements Vol 87 Issue 2260supp" srcSet="https://static.scientificamerican.com/sciam/cache/file/D9E45E6A-C03B-4B06-856D5FDAFDB341A9_source.gif?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/D9E45E6A-C03B-4B06-856D5FDAFDB341A9_source.gif?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Supplements</h3><div class="issue__date-ozuG1"><time dateTime="1919-04-26">April 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/sa/1919/04-26/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/63D4A00D-E60F-4D70-978E4A4CB06F8B98_source.jpg?w=600" alt="Scientific American Magazine Vol 120 Issue 17" srcSet="https://static.scientificamerican.com/sciam/cache/file/63D4A00D-E60F-4D70-978E4A4CB06F8B98_source.jpg?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/63D4A00D-E60F-4D70-978E4A4CB06F8B98_source.jpg?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Scientific American</h3><div class="issue__date-ozuG1"><time dateTime="1919-04-26">April 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/supplements/1919/04-19/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/EC04F8CC-DC61-458F-8241A96B5068FE70_source.gif?w=600" alt="SA Supplements Vol 87 Issue 2259supp" srcSet="https://static.scientificamerican.com/sciam/cache/file/EC04F8CC-DC61-458F-8241A96B5068FE70_source.gif?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/EC04F8CC-DC61-458F-8241A96B5068FE70_source.gif?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Supplements</h3><div class="issue__date-ozuG1"><time dateTime="1919-04-19">April 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/sa/1919/04-19/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/C8E7B1C5-7842-4FBE-AE6AEDF3DFD00371_source.jpg?w=600" alt="Scientific American Magazine Vol 120 Issue 16" srcSet="https://static.scientificamerican.com/sciam/cache/file/C8E7B1C5-7842-4FBE-AE6AEDF3DFD00371_source.jpg?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/C8E7B1C5-7842-4FBE-AE6AEDF3DFD00371_source.jpg?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Scientific American</h3><div class="issue__date-ozuG1"><time dateTime="1919-04-19">April 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/supplements/1919/04-12/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/06D3531B-DDB0-4F38-8EAB8DD1B1813813_source.gif?w=600" alt="SA Supplements Vol 87 Issue 2258supp" srcSet="https://static.scientificamerican.com/sciam/cache/file/06D3531B-DDB0-4F38-8EAB8DD1B1813813_source.gif?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/06D3531B-DDB0-4F38-8EAB8DD1B1813813_source.gif?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Supplements</h3><div class="issue__date-ozuG1"><time dateTime="1919-04-12">April 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/sa/1919/04-12/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/33357B61-3F5A-479A-A5C93BA91E2526D1_source.jpg?w=600" alt="Scientific American Magazine Vol 120 Issue 15" srcSet="https://static.scientificamerican.com/sciam/cache/file/33357B61-3F5A-479A-A5C93BA91E2526D1_source.jpg?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/33357B61-3F5A-479A-A5C93BA91E2526D1_source.jpg?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Scientific American</h3><div class="issue__date-ozuG1"><time dateTime="1919-04-12">April 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/supplements/1919/04-05/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/E8883656-3D84-4B81-8FDB78EBADE09EC1_source.gif?w=600" alt="SA Supplements Vol 87 Issue 2257supp" srcSet="https://static.scientificamerican.com/sciam/cache/file/E8883656-3D84-4B81-8FDB78EBADE09EC1_source.gif?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/E8883656-3D84-4B81-8FDB78EBADE09EC1_source.gif?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Supplements</h3><div class="issue__date-ozuG1"><time dateTime="1919-04-05">April 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/sa/1919/04-05/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/845C6E35-8EA5-462F-BCF01E6AAEDDF617_source.jpg?w=600" alt="Scientific American Magazine Vol 120 Issue 14" srcSet="https://static.scientificamerican.com/sciam/cache/file/845C6E35-8EA5-462F-BCF01E6AAEDDF617_source.jpg?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/845C6E35-8EA5-462F-BCF01E6AAEDDF617_source.jpg?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Scientific American</h3><div class="issue__date-ozuG1"><time dateTime="1919-04-05">April 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/supplements/1919/03-29/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/8B6F480B-1156-47F9-9BD57D3EE2D198E9_source.gif?w=600" alt="SA Supplements Vol 87 Issue 2256supp" srcSet="https://static.scientificamerican.com/sciam/cache/file/8B6F480B-1156-47F9-9BD57D3EE2D198E9_source.gif?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/8B6F480B-1156-47F9-9BD57D3EE2D198E9_source.gif?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Supplements</h3><div class="issue__date-ozuG1"><time dateTime="1919-03-29">March 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/sa/1919/03-29/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/FEEB84A0-8394-4100-B6BC7BA6F798E635_source.jpg?w=600" alt="Scientific American Magazine Vol 120 Issue 13" srcSet="https://static.scientificamerican.com/sciam/cache/file/FEEB84A0-8394-4100-B6BC7BA6F798E635_source.jpg?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/FEEB84A0-8394-4100-B6BC7BA6F798E635_source.jpg?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Scientific American</h3><div class="issue__date-ozuG1"><time dateTime="1919-03-29">March 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/supplements/1919/03-22/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/17B02123-B978-4376-B1B2FDD14E46F7D4_source.gif?w=600" alt="SA Supplements Vol 87 Issue 2255supp" srcSet="https://static.scientificamerican.com/sciam/cache/file/17B02123-B978-4376-B1B2FDD14E46F7D4_source.gif?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/17B02123-B978-4376-B1B2FDD14E46F7D4_source.gif?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Supplements</h3><div class="issue__date-ozuG1"><time dateTime="1919-03-22">March 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/sa/1919/03-22/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/8F6B8C87-179C-45FB-9BAE8731954ACA4E_source.jpg?w=600" alt="Scientific American Magazine Vol 120 Issue 12" srcSet="https://static.scientificamerican.com/sciam/cache/file/8F6B8C87-179C-45FB-9BAE8731954ACA4E_source.jpg?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/8F6B8C87-179C-45FB-9BAE8731954ACA4E_source.jpg?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Scientific American</h3><div class="issue__date-ozuG1"><time dateTime="1919-03-22">March 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/supplements/1919/03-15/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" 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loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Scientific American</h3><div class="issue__date-ozuG1"><time dateTime="1919-03-08">March 1919</time></div></div></div></a></div><div class="list__item--tR3J"><a class="issue__link-3e-qg" href="/issue/supplements/1919/03-01/"><div class="issue-VnvuN"><div><div><figure class="issueImageContainer-WnIB2"><img class="issue__cover__image-35p5E" src="https://static.scientificamerican.com/sciam/cache/file/78D034FA-7E1C-4A30-BF81C0255A0735D3_source.gif?w=600" alt="SA Supplements Vol 87 Issue 2252supp" srcSet="https://static.scientificamerican.com/sciam/cache/file/78D034FA-7E1C-4A30-BF81C0255A0735D3_source.gif?w=300 300w, https://static.scientificamerican.com/sciam/cache/file/78D034FA-7E1C-4A30-BF81C0255A0735D3_source.gif?w=600 600w" sizes="300px" width="300" loading="lazy"/></figure></div></div><div class="issue__info-Wrv5W"><h3 class="issue__title-rRMdq">Supplements</h3><div 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