(2094- 
Fig. 2. Cares, If the Station be one of the Sides of the Tri- 
angle, as in the Second figure at<y, then having the three 
fides A Cj CB^B A, given, find the angle C A B then a- 
gain in the Triangle SAB all the Angles, and the fide AB 
are kno wo^ whence may be found either A S oxS B, Ceome- 
trically^ if you make the angle CAD equal to the obferved 
angle C s B^ and draw B S parallel to D A^ you determine 
the Point of Station S> 
Cafe 3. Ifthethree Objedslie in a right Line zsACB 
(Suppofe it done^) & that a Circle paffeth through the Sta- 
tion S^^nd the two exteriour Objefts A Bixhen is the Angle 
A B D equal to the obferved angle ASC (by 2 i of the gd. 
book of Euclid,) as infifting on the fame Arch A D : And the 
Angle BAD in like manner equal to the obferved Angle 
CSBihy this means thepointD is dctermined.Joyn £) C, and 
produce the fame, then a Circle paffing through the 
Points A BDy interfefts D C, produced at Sy the place of 
Station. 
Calculation. 
In the Triangle ABD all the Angles and the fide A B 
are known, whence may be found the fide A D, 
Then in the Triangle C A D.the tvvo Sides CAzndAD 
are known, and their contained angle C AD is known, 
whence, may be found the Angles C D A and A C D^ the 
complement vi/hereof to a Semicircle is the angle S C A : in 
which Triangle the Angles are nmvall known -iind the fide 
AC : vv^hence may be found either of the DiftapceSj S € or 
S A. 
Fig4, Cafe 4* If the Station be n?///?*^;// the Triangle, made by 
the Ob jeftsj the fum of the Angles obferved is lefs than four 
right Angles* The Conflruftion is the fame as in the laft ^ 
Cafr, and the Calculation likewife 5 lavitog that you mufl: 
make one Operation more, having the three Sides^ C 
B thereby find the angle C which add to the Anf>Ie 
E A D then you have the two iidQ^^vi^. AC ^ being one of the 
DiftanceS; and ^ (found as in the former Cafe) with their 
contained 
