PHYSICAL anp LITERARY. 137 
fum of the angles, CSB, CB&, to the tan- 
‘gent of half the difference of the angles 
CSB, CBS. 
The log. tang. of 30° is 9.7614394 
The log. of 7941t is 4.8998807 
The fum is 14.6613201 
The log. of 120589 is 50813077 
ween ee 
The difference 9.58001 24 is the 
log. tang. of 20° 49’.00894, half the dif- 
ference of the angles CSB, CBS; therefore 
the angle CSB or ACD is 50° 49’.00894, 
and the angle CBS or BCD is 9°10’.991 06. 
Again, in the triangle DCS, as 120589 the 
fum of DC, CS, isto 79414 the difference 
of DC, CS, fo is the tangent of 25° 
.24'.50447 half the fum of the angles, 
CSD, CDS, to the tangent of half the dif- 
ference of the angles CSD, CDS. | 
Vo1, Il. S | The 
