fcope, 14; his compound microfcope defcribed, 16 ; his
method of meafuring the magnifying power of the compound,
microfcope, 58; his method o f fixing objefits intended to be
drawn, lgg.
Hill, Sir John, his mode o f preparing branches o f trees for ob-
fervation, 158, 162.
Hemerobius perla defcribed, 373.
Hydra, many fpecies of defcribed, 398; their food, and method!
of feizing their prey, 409; generation of, 415.
I
Janfens and Son, microfcopes made by them, 2.
Infefils, a fcientific account of, 167 ; antennae of defcribed, 175;-
legs ditto, 179 ; wings ditto, 182; particular charafters : of*
185; how elafled by Linnaeus, 187 their transformation, 189;
the larva of, 193; pupa of, 197; their refpiration, 240;
generation of, 248; eggs of, 265, 269; their multiplication,
271; food of, 272 ; habitation of, 278 ; wings of, 367; elytra,
of, 368.; eyes of ditto, 375.
L
Lieberkuhn, Dr. his microfcope defcribed, 7 ; his folar ditto;
Leeuwenhoeck’s microfcopes ditto, 7.
Lucemal microfcope, invented by G. Adams, 22 ; it’s peculiar
advantages, 65 ; fully defcribed, 67.
Light rays ufed as a folar microfcope, 78; it’s apparatus, 79 ;
experiment made with, 29; o f the management o f the, 131..
Lenfes;,
1
7 t 7
Lenfes, the various forts defcribed, 37 ; their ufes, 38, 39, 40.
Lanthorn, added to the lucemal microfcope, 67.
Lamp, Argand’s, defcribed, 70.
Lyonet’s anatomical microfcope defcribed, 114; his mode of
preparing objefils, 138, 139,
Libellula defcribed, 231; it’s eye defcribed, 382,
Lepas anatifera defcribed, 359.
Leucofpis dorfigera defcribed, 385,
Lobfter infefit defcribed, 386.
Loufe defcribed, 698.
Lump-fifh, fkin of, 388,
M
Microfcopes, firft invention of, 1 ; claimed by the Dutch and!
Italians, ibid, their ufe, 2; made by Zacharias Janfen and his
Son, ibid, defeription of one defcribed by Aepinus, 3; known
to the Greeks and Romans, ibid, Angle microfcope defcribed,.
§ ; further explained, 44; magnifying power of, 45; improved
b y . Lieberkuhn, 66; ditto by Leeuw-enhoeck, 7 ; fmall
glafs globules ufed inftead o f convex lenfes, 8 ; globules o f
water ditto, 13 ; two drops o f water, 1.4 ; compound o f Dr.
Hooke defcribed,. 16; Euftachio Divini’s ditto, 16 ; Philip
Bonnani’s ditto, 17; compound, improved by Dr. Robert
Barker, 18'; by Dr. Smith, 18; explained fully, 46 - folar,
invented by Lieberkuhn; 19; explained, 49; fully defcribed,
99; lucemal, invented.by G. Adams, 22; its peculiar
advantages,. 65, 67 ; fully defcribed, 67 ; ufed as a folar, 78 ;
Delebarre’s, 23 ; the different forts referred to, 24 ; their magnifying
power, §3 ; Cuff’s double-conflru filed defcribed, 80:
Adams’s improved double and Angle, 83; improved compound,