Termites defcribed, 292.
Timber, organization of, 652.
Thrips phyfapus defcribed, 387.
Tubularia, a fpecies o f polype defcribed, 449.
V
Vifion, the nature of, 28 ; in the eye, 31.
Vegetables, manner o f preparing, 157.
Vorticellse, many fpecies o f defcribed, 433.
Veffels between the bark and rind o f trees, 659; fap, 674 ; in-
moft, 675.
W
Water, globules of, ufed as microfcopes by Mr, Gray, 13; two
drops of, 34.
"Willbn s pocket- microfcope defcribed, 103; improved by a
fcrole, 10 6.
Withering, Dr. his botanical microfcope, 113.
Wafp, themafon ichneumon, 286.
Wings o f infe&s, 367 ; o f the moth and butterfly, 370 ; motion
o f ditto, 372; o f the hemerobius perla, 373 ■ of the earwig,
374-
Wood confidered, 668,
A C a t a -
€ A T A L O G U E
'0 F
Mathematical and Philofophical Inftruments,
MADE AND SOLD BY
G E O R G E A D A M S ,
Mathematical Inftrument Maker to His Majesty,
No. 60, Fleet-Street) London.
Optical Inftruments
T£■ ITE beft double-jointed filver fpe£tacles, with glafles «— 1 1 o
: The beft ditto,, with Brazil pebbles- -------- i 16 o
Single joint filver fpe&aeles, with glafles . — — o 15 o
Ditto, with Brazil pebbles — *—* 1 1 0 0
Double joint fteel fpeftacles, with glafles -------- o 10 6
Another fort of ditto. — — o 7 6
JBeft fmgle-joint fpe£tacles ■— — .0 5 0
Ditto» inferior frames — -1- ' — o 3 6
Nofe fpe£tacles, mounted in filver — ’ , 0 7 o
Ditto in tortoifelhell and filver — . *—* o 4 0
Ditto in horn and ft eel -7— - 0 1 0
’Spectacles for couched eyes
SpeCtacles with fhades
Concave glafles in horn boxes, for fhort-fighted eyes
Ditto mounted in tortoifelhell and filver, pearl and filver, in various
manners, and at different prices
Reading glafles, "from 2s. 6d. to —- - — -— 2 2 0
•Opera glafles, from 10s. 6d. to — — * 2 0
Ditto of an. improved coriftruCtion —- ■ 1 . 1 o
Concave and convex mirrors .in frames, from 7s. -6d. to — 18 18 o
4 T Telefcopes
i rJl