89 
'SFv r * 
= (v — • v) . V — l • 
« 
m 
z 4“ n 
. Sin z 9 — • etc.r , 
vel , ob exiguitatem anguli 9 et posito oc = 
w 
m 
9 2 
• » > 
2 (z+n) 
» ss (v — 1/) (z — cc) et v — 3 =b 1/ 4- a (1/ — v) } quæ 
æquatio cum XI comparata subministrat 
ix 
h c 
XV 
{v -+- oc v — et v) 
2 4- Z 
i . cc ix 
= XV ( i — — — — 
Z + Z 2 4- Z 
(z/ — a v) 
rel tandem, ob exiguum ipsius oc . z/ valorem. 
he a ( z — ) — - 
v )+/ 2 
#1/. 
if//. 
§. 19. 
Hisce præstructis, via ad præcipuum hujus disquisitionis 
argumentum explicandum patet. 
Summa omnis lineæ mediae CO ante planum majoris densi- 
tatis (compacturae) est = J — pdx, ab x zrz CO =: K usque 
ad X —3 0 sumta. Valor ipsius p ex æqu. IX sumendus est. 
Ductâ TT H (fig. .18) ipsi A O parallela, facile patebit, omnem 
compacturam, quæ inter C et H locum habet, in situ tantum- 
modo curræ BPn constituendo collocari atque adeo ad nihilum 
12 
