Editing Alvan Clark (section)

==Biography==
Born in [[Ashfield, Massachusetts]], Clark started as a portrait painter and engraver (c.1830s–1850s), and at the age of 40 became involved in telescope making. Using glass blanks made by [[Chance Brothers]] of Birmingham, England, and [[Feil-Mantois]] of Paris, France, his firm [[Alvan Clark & Sons]] ground lenses for [[refracting telescope]]s. Their lenses included the largest in the world at the time: the {{convert|18.5|in|cm|sing=on}} at [[Dearborn Observatory]] at the [[Old University of Chicago]] (the lens originally intended for [[Ole Miss]]); also the two {{convert|26|in|cm|sing=on}} telescopes at the [[United States Naval Observatory]] and [[McCormick Observatory]], the {{convert|30|in|cm|sing=on}} at [[Pulkovo Observatory]], which was destroyed in the [[Siege of Leningrad]] (only the lens survives), the {{convert|36|in|cm|sing=on}} telescope at [[Lick Observatory]] (still the third-largest), and later the {{convert|40|in|cm|sing=on}} at [[Yerkes Observatory]], which remains the largest successful refracting telescope in the world.

Although not specifically searching for [[double star]]s, he did make a number of discoveries while testing his completed telescope objectives,<ref>{{cite book | title=An Anthology of Visual Double Stars | first1=Bob | last1=Argyle | first2=Mike | last2=Swan | first3=Andrew | last3=James | page=288 | isbn=9781108601702 | publisher=Cambridge University Press | date=2019 | url=https://books.google.com/books?id=jSmqDwAAQBAJ&pg=PT288 }}</ref> including [[Mu Herculis]], [[8 Sextantis]], and 95 Ceti.<ref>{{cite journal | title=New Double Stars, with remarks | last1=Clark | first1=A. | last2=Dawes | first2=W. R. | journal=Monthly Notices of the Royal Astronomical Society | volume=17 | page=257 | date=June 1857 | doi=10.1093/mnras/17.9.257 | bibcode=1857MNRAS..17..257C | doi-access=free }}</ref> One of Clark's sons, [[Alvan Graham Clark]], discovered the dim companion of [[Sirius]]. Two [[Impact crater|craters]] bear Clark Sr.'s name. The crater [[Clark (lunar crater)|Clark]] on the [[Moon]] is jointly named for him and his son, Alvan Graham Clark, and one on [[Mars]] is named in his honour.<ref name=deVaucouleurs1975>{{cite journal | title=The new Martian nomenclature of the International Astronomical Union | display-authors=1 | last1=de Vaucouleurs | first1=G. | last2=Blunck | first2=J. | last3=Davies | first3=M. | last4=Dollfus | first4=A. | last5=Koval | first5=I. K. | last6=Kuiper | first6=G. P. | last7=Masursky | first7=H. | last8=Miyamoto | first8=S. | last9=Moroz | first9=V. I. | last10=Sagan | first10=Carl | last11=Smith | first11=Bradford | journal=Icarus | volume=26 | issue=1 | date=September 1975 | pages=85−98 | doi=10.1016/0019-1035(75)90146-3 | bibcode=1975Icar...26...85D }}</ref> His other son was [[George Bassett Clark]]; both sons were partners in the firm.

Clark was also competitive in target shooting and received a patent for his device to allow bullets to be seated into a muzzle-loading rifle without damage to either the bullet or the rifle's muzzle. Exclusive license to this patent (1,565 of April 24, 1840) was made to Edwin Wesson, brother of [[Daniel B. Wesson]].<ref>{{ cite journal | last = Hamilton | first = John D. | journal = American Society of Arms Collectors Bulletin | title = Alvan Clark and the False Muzzle | issue = 79 | pages = 31–37 }}</ref>

In 1880, Clark was elected as a member to the [[American Philosophical Society]].<ref>{{Cite web|title=APS Members History|url=https://search.amphilsoc.org/memhist/search?year=1880];smode=advanced;startDoc=1|url-status=live|archive-url=https://web.archive.org/web/20210514152905/https://search.amphilsoc.org/memhist/search?year=1880%5D;smode=advanced;startDoc=1 |archive-date=May 14, 2021 }}</ref>

[[File:Lowell Observatory - Clark telescope.jpg|thumb|right|Alvan Clark Refractor Telescope at [[Lowell Observatory]]]]