718 



INDEX. 



pound, 89; Culpeper's, or three-pillar'd, ibid, improved 

 folar, 92 ; fcrew-barrel, or Wilfon's Tingle pocket, 103 ; fcrole 

 and mirror added to it, 106; fmall for opake objects, 107; 

 Ellis's aquatic, 110; anatomical of Lyonet, 114; botanical 

 of Dr. Withering, 115; common ditto, 116; and telefcope, a 

 portable one defcribed, 118; the neceflary preparation for 

 obfervation, 128. 

 Medium, what, 24 ; rare, and denfe, ibid. r 

 Magnifying power of microfcopes, how to meafure, 54. 

 Magnifiers, botanical, 117. 



Magny, Mr. his method of meafuring the magnifying power of 



lenfes, 55. 

 Micrometer, the needle defcribed, 59. 

 Mufca chameleon, it's changes defcribed, 220. 

 Motion of the wings of infefts defcribed, 372. 

 Monoculus polyphemus, or king-crab, eyes of, 383 ; apus ? 



39 1 - 



Meloe monoceros defcribed, 390. 



N 



Needle micrometer, 59. 



O 



Objeds, opake, how examined in the lucernal microfcope, 73 ; 

 catalogue of, 688 ; tranfparent ditto, 76 ; catalogue of, 693 \ 

 mode of preparation, 134, 148. 



Polypes, 



