CHAP. I. The Elplanation and Ʋse of the Table of SINES.
BEfore I come to the mensuration of Triangles, it will be necessary to explain and shew the use of the Tables of Sines and Logarithms following, by which Tables the sides or angles of right lined Triangles may be readily and exactly measured, so that in any plain Triangle, if there be any three parts thereof gi∣ven, a fourth may be easily discove∣red.
The Table of Sines consisteth of two Rows or Columns, the first whereof sheweth the Degrees and Minutes of the Quadrant, having over the head thereof these two letters, D. M, standing for Degrees and Minutes: In the second Column is the Artificiall Sines answering to every Degree, and 10th Minute of the Quadrant, having the word Sine over the head thereof. The use of this Ta∣ble will appear by the following Propositions.
PROP. I. Any Degree and Minute being given, to finde the Sine thereof.
FIrst, Seeke the Degree and minute in the first Columne of the Table, under D. M. and right against it, in the next Column towards the right hand, under the word Sine, you shall have your desire.