Alvan Graham Clark was as deeply involved in the family business 

 as was George. In talent and temperament, however, the brothers dif- 

 fered considerably. 23 While George did mechanical work, Alvan Graham, 

 with an eye as keen as his father's, figured and tested the object glasses. 

 George was little known outside his work ; Alvan Graham is described as 

 unusually attractive in both social intercourse and personal appearance. 

 He was fond of the companionship of intelligent men, poets as well as 

 scientists, personal friends as well as casual visitors. With a love for litera- 

 ture, and a remarkably retentive memory, Alvan Graham could, and 

 apparently did, quote from the poets "almost indefinitely." His sociability 

 was doubtless enhanced by his wife, Mary Mitchell Willard, a member 

 of a large and influential Cambridge-Harvard family. 



Alvan Graham was born in Fall River in 1832. As a schoolboy in 

 East Cambridge, at the time of his father's first telescope experiments, 

 he wrote prize essays on the casting and grinding of mirrors. 24 At age 

 sixteen he entered a machine shop, where he spent four or five years 

 learning the machinist's trade before entering the family firm. While 

 testing object glasses Alvan Graham discovered a number of interesting 

 and difficult double stars; the most famous, the companion of Sirius, 

 earned him the 1 862 Lalande Prize of the Paris Academie des Sciences. 25 

 He joined the American Association for the Advancement of Science in 

 1879 and the following year was elected to fellowship; in 1881 he became 

 a resident fellow of the American Academy of Arts and Sciences; in 1894 

 he was elected a member of the Societe Astronomique de France. 26 



The first astronomical instruments Alvan Clark worked with were 

 metal reflectors, as they were reputedly easier than refractors. He seems 

 to have made a number of these telescopes, with apertures as large as 8 

 inches. During the winter of 1847-48, using a freshly polished 7j/ 2 -inch 

 speculum, he made a diagram of the stars in the Orion Nebula. To 

 guarantee the honesty of his observations, he refrained from studying 

 previous maps until he had drawn his own. 27 William Cranch Bond, 



23 Most available biographical information on Alvan Graham Clark is in his 

 obituary in Proc, American Academy of Arts and Sciences, vol. 33 (1897-1898), pp. 

 520-524. 



24 "Alvan Graham Clark," Dictionary of American Biography (New York, 1930), 

 vol. 4, p. 120. 



25 Comptes Rendus, Academie des Sciences, vol. 55 (1862), pp. 936-937. 



26 Bulletin, Societe Astronomique de France, vol. 1 1 (1897), p. 300. 



27 Alvan Clark, "Telescopes," The Boston Courier, 13 November 1848. 



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