Mathematical Inftruments. g 
render them not unworthy of a place in the cabi¬ 
nets of the curious. 
That their exaftnefs may be particularly attend¬ 
ed to, I always infpedt and direbt the feveral pieces 
myfelf, fee them all combined in my own houfe, 
and finifh the moft curious parts thereof with my 
own hands. That the conftrudion may be as fim- 
ple and fubftantial as the ufe of each inftrument 
will admit, it is my conftant ftudy to contrive 
them in l’uch a manner that they may be managed 
with the greateft eale. I alfo have refpect to their 
being made applicable to feveral operations, efpe- 
cially when the extent of their ufes does not pre¬ 
judice their fimplicity, to the end that inftruments 
may not be multiplied without necefiity. 
In the following catalogue I have ranged the 
inftruments in claffes under the heads of their fe¬ 
veral branches, and have numbered each particular 
inftrumenr, fo that if a gentleman is aefirous of 
any one or more of them,' and is at any diftance 
from London, he need only fend me the numbers 
adjoining to thofe he intends to purchafe, and he 
fnali be ferved with fidelity, and at the lowefl 
prices. 
Inftruments for Geometry, Drawing, &c. 
V Ariety of pocket cafes of drawing inftruments, 
in filver, brais, ivory, or v/ood, from 10s. 
6d. to 5I. 5s. Thefe contain more or Ids of the 
following articles, which limit their price, 
i Plain compaftes for meafuring lines, &c. 
2 Drawing compaftes, with moveabie points, 
viz. an ink point for fweeping circles, or 
arches of any determinate tkicknefs, and 
a black lead point. 
3. Drawing 
