,^ 



HOLCOMB,FITZ,ancl PEATE 



Three \9th Centuri) American 

 Telescope Makers 



Practically all the telescopes used by amateur scientists in 18th- 

 century America ivere of European origin. Our dependence upon 

 foreign sources for these instruments continued ivell into the 19th 

 century, and the beginning of telescope making in this country has 

 conventionally been associated ivith the names of Alvan Clark and 

 John Bra shear, ivhose work dates from the I860' s. 



Presented here are biographical sketches of tivo predecessors and a 

 co7jtemporary of Clark and Brashear ivhose obscurity is not deserved. 

 The accounts relate some hitherto little-known aspects of tele- 

 scope making in America as it progressed from mechanic art to science. 



The Author of the Introduction, Kobert P. M.ulthauf, is head 

 curator of the department of science and technology in the United 

 States ISlational M.useum, Smithsonian Institution. 



Introduction 



Kobert P. Multhauf 



THE TELESCOPE was invented about 1600. It was 

 brought to America about a half-century later, 

 and within another century had become a common- 

 place appurtenance to the library of the cultivated 

 gentleman.' 



Throughout this period, from Galileo to Herschel, 

 the telescope found use in scientific astronomy, al- 

 though the possibility of contributing to the science 



' Instruments surviving from 18th-century America are 

 almost exclusively of European origin, products of the nu- 

 merous and famous shops which sprang up, particularly in 

 England and France, to meet the demand occasioned by the 

 popularity of the telescope among amateurs and dilettanti. 



of astronomy by simple observation diminished con- 

 tinuously after the time of Galileo. Herschel's work 

 had aimed at the advancement of scientific astronomy 

 through increasing spectacularly our powers of 

 vision, just as had that of Galileo in the 17th century 

 and of Hale in the 20th. But even in Herschel's 

 time the monstrous size of the instrument required 

 made the project something of a national effort. 

 The telescopes of the 18th-century American gentle- 

 man were already toys, as far as the astronomer was 

 concerned. 



However, the telescope had another, if less glamor- 

 ous, use in the 18th century. This was its use in 

 positional astronomy, in the ever m.ore precise meas- 

 urement of the relative positions of objects seen in the 

 heavens. Measurement had been the purpose served 

 by pre-telescopic astronomical instruments, the sight- 

 ing bars of the Ptolemaic observers of Alexandria and 

 the elegant quadrants of Tycho Brahe. For a time 



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BULLETIN 228: CONTRIBUTIONS FROM THE MUSEUM OF HISTORY AND TECHNOLOGY 



