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CO f. P 
§ 5. It likewife appears to me, that fince-—^-^ 
cof. A 
fin. p 
•and therefore tang. ^/= 
tang. D fin. j> „ 
iin. P fin. — ““6- — fi„. P (in. A’ 0 
nomers ought no lefs to employ this laft formula, than 
any other more troublefome, in practical computation. 
The fimpleft is tang, d — : IT r \ upon the 
fuppofition of an exadt table of the parallaxes of 
altitudes ready made; and I believe it will be 
as eafy to compute with tangents as with arches, 
by means of logarithms; and therefore this Ampli- 
fication in putting arches inflead of tangents is 
unnecedary. 
§ 6. To try the confequences of this theory, I made 
A=30°, D— 15^ and taking the vertical of Upfal to 
the terreflrial axis for the radius of the fphere, I found 
p— 35',io // , 3, fuppofing that the axis of the earth, 
is to the diameter of the equator as 1 99 to 200, and by 
j tang. D fin. A 4 -p tang. D cof. p 
the formulas tang. d = — Pc 7Ta 
tiu^J^fnng j £ oun( J < /_ I .' 12". 664, but by 
the formula d— 7 — — — - — I had dz=. id, 12", 
67 c. and laflly by that of Euler d— . — - — 
we have d— 1 5', 1 2", 635 ; from whence it appears 
that the error is very fmall, but that with the fame 
trouble one may avoid any error whatfoever. 
§ 7. The prefent cale did not give an error of 
o // ,oo 1 in fubflituting 1 or the radius inflead of cof. 
p. Hence I conclude that dz=z 7 — r » will be 
* . 1 — fin. i cof. A 
a more 
