wich Observatory, and the June meeting of the Royal Astronomical 

 Society, where he met Sir John Herschel and Lord Rosse. At the R.A.S. 

 meeting Alvan Clark exhibited an improved double eyepiece micrometer 

 wherein the distance between the two separate eyelenses was measured 

 by movable, parallel spider lines mounted in front of the eyepieces. 55 

 One evening, while using the 8-inch-aperture equatorial refractor he 

 had just brought to Dawes, Clark discovered the duplicity of 99 Herculis. 

 In reply to Mrs. Dawes, who asked what made him think this star had 

 not yet been charted, Alvan Clark said, "I thought it too fine for any- 

 body else." 56 



During his lifetime, undoubtedly in recognition of work done by 

 Alvan Clark & Sons, Alvan Clark received four honorary Master of Arts 

 degrees and two special medals. 57 The first degree came from Amherst 

 College in 1854 when the Clarks made a 7^2-inch refractor for that 

 school. Princeton conferred a similar degree in 1865. The old Univer- 

 sity of Chicago gave him an honorary degree in 1866, the year the 181/2- 

 inch was installed in Chicago. Alvan Clark was for many years on the 

 visiting committee of the Harvard College Observatory; in 1874 Har- 

 vard made him a Master, with the words, Artificem egregium, specu- 

 latorem rerum coelestium callidum. 5s It is related that when Dom Pedro, 

 the Brazilian emperor, was in Cambridge in 1876, he wished to see 

 only three persons: Henry Wadsworth Longfellow, Louis Agassiz, and 

 Alvan Clark. 59 On the suggestion of Otto Struve, Czar Alexander III of 

 Russia in 1885 granted Alvan Clark a medal "in acknowledgment of 

 the excellent performance of the great [Pulkowa] object-glass." This 

 medal was of solid gold, %6-inch thick and 3^ inches in diameter. 60 

 Alvan Clark's other great honor, which came in 1867, was the rarely 



55 "Mr. Alvan Clark's New Micrometer for Measuring Large Distances," Monthly 

 Notices, Royal Astronomical Society, vol. 19 (1859), p. 324. 



56 Quoted in Garth Galbraith, "The American Telescope Makers," op. cit. 



57 Alvan Clark autobiography, op. cit., pp. 116-117. 



58 Quoted in private correspondence with Kimball C. Elkins of the Harvard 

 University Archives. 



59 "Alvan Clark," National Cyclopaedia of American Biography (New York, 1929), 

 vol. 6, p. 440. 



60 Otto Struve to Alvan Clark & Sons, 23 July 1885, quoted in Appleton's Annual 

 Cyclopaedia, vol. 10 (1885), pp. 54-55. See also Scientific American, vol. 53 (1885), 

 p. 304, and Science, vol. 7 (1886), p. 350. 



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