xviii The Mi cr of cope explained. 
nefs obtained. Side-faces in imitation of fhadows, are 
likewife taken this way to great advantage. 
Let the perfon, whofe portrait or fide-face is defiled, 
fit on a chair, at the diftance the pidture was placed at, 
and keep himfelf as ftill as pofiible. 
The human attitude, in any pofition, may be admirably 
well delineated after the fame manner. 
Fourthly, pieces of ftill life, fuch as flowers, fruits, 
dead game, &c. may be elegantly copied this way, by 
fetting them upon a ftool, that is lower than the table, 
and pointing the inftrument to your objedfc. 
All forts of furniture, workmanfhip of every kind, 
fuch as mathematical inftruments, models, bulls, china, 
or other images, &c. may be alfo delineated in the fame- 
manner. 
The third application of the camera obfcura, is to re- 
prefent objedts in their natural fituation witnout reflec¬ 
tion. The preparation for this is as follows : take out 
the fquare Hiding tube P Q, and place that convex lens, 
which is marked with No. 4. into that end of it which 
is alfo marked No. 4. and goes into the camera; then 
replace it again, as it appears in fig. 9* an ^ P u t the tube 
W Z into the hole at P, until the fhoulder m n, refts 
clofe to the furface at P, and the inftrument will be 
ready for ufe. 
In this ftrudture of the camera, it may be applied to 
all the experiments, related in the preceding application p 
but the field of view will not be quite fo large ; yet in 
this we have many advantages, from the objedls appear- 
ing in their natural fituation. 
See fig. 8. in which ADEB reprefents one fide of 
the pyramidical camera obfcura; AGO, the front; 
pQ, a fquare tube, which may be moved higher or 
lower, by turning the knob at f, in order to adjuft the 
focus of the convex lens placed at d, to make a diftindt 
piaure at the bottom of the inftrument; abc is the 
r opening. 
