SHORTER ARTICLES AND CORRESPONDENCE 



AN EIGHTEENTH CENTURY MICROSCOPE 1 



Early microscopes are uncommon and our knowledge of the 

 sequence of their forms is in part to be gained by random dis- 

 coveries. The instrument shown in the figure was obtained 

 recently from the antiquary Meyer in Zurich (who said that it 

 had formed part of the collection of Sir Henry Angst), and it 

 is worthy of comment, both for its early date, and its admirable 

 preservation. 



It dates, in all probability, from the early years of the eight- 

 eenth century. It resembles in essential regards John Mar- 

 shall's 2 microscope of about 1700 and Hertel's 3 of 1716. Indeed 

 it may possibly be slightly earlier than the Marshall instrument, 

 for in some regards it is more archaic. Thus it conserves the 

 tripod-shaped support, and lacks the mechanical focusing adjust- 

 ment. It is, moreover, not an instrument of common class in 

 which such features would be retained at a late date by reason 

 of economy, for its workmanship is throughout precise and ele- 

 gant. On the other hand, it is furnished with a sub-stage mirror 

 which sm'-iresfs n transitional form to the Hertel stand. The 

 stage and the supports of the barrel are of brass, as well also as 

 the upper rim of the eyepiece, which is provided with a dust- 

 proof sliding cover, as in early spy-glasses. The barrel and its 

 supporting tube are of carton ; the former is covered with green 

 paper which bears rings as guides for focusing, and gilt bands, 

 the latter is decorated with Chinese shagreen. The base of the 

 barrel, the mounting of the objectives and the region of the eye- 

 piece are of ebony. The base of the stand is octagonal, orna- 

 mented with moulding and furnished with a drawer for acces- 

 sories. It is quite similar to the Marshall instrument in this re- 

 gard, and in the turned supports of the eyepiece and of the ob- 



There is but one eyepiece, its lenses measuring 1 inch and 

 If inches in diameter, and it can not be removed from the stand. 



1 Kecently presented to the American Museum of Natural History. 



*Cf. Harris's "Lexicon Technicum," 1704, and figured by Carpenter 

 (VII. ed.), 1891, p. 136. 



•Op. ext., pp. 137-138. 



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