34 7e Vg oft eli Line of Superficies.

ſame Scale with the ſecond Number, ſhall give the fourth Number re-uired.

5 As if a Field contained 28 8 Acres when it was meaſured with a Sta-cute Perch of 161, and being meaſured with another Perch, was found to

contain 242 Acres, it were required to ænow hat was che length of thePerch with which it was ſo meaſured.

lere becauſe the Proportion is reciprocal, if I took 16 4 out of chethe Line of Lines, and put it over in 242 in the Lines of Superficies, hisParallel between 288 and 288, being meaſured in the Line of Lines,would be 18, and ſuch is the lengch of the Perch(in Feet) Where wich theField was laſt meaſured.

For ſeeing the Proportion of the Acres is as 28 8 unto 242, or inthe leaſt Numbers, às 144 to 121, and that the Root of 144 is 12and the Root of 12 1 is 11, the Proportion of Roots, and conſequentiyof the Perches, ſhall be as 12 to 12, and ſo are 16 4 to 18 in reciprocalProportion.

If 360 men were te be ſet in form of a long Square, whoſe Sidesſhall have the Proportion of 5 to 8; and it were required to Know the

Number of men to be placed in front and file: If che Sides were only5 and 8, chere ſnould be but 40 men; but there are 360: thereforeworking as before, I find that, 9 0 7

As 4 to the Jquart f 10 So 360 to the Square of 15.

A, 40 to the Square f 82:a So 360 to the Squre ¶ 24.and ſo 15 and 24 are the Sides required.

If 1000 men were lodged in à ſquare ground whoſe Side were 60paces, and it were required to know che Side of che Square wherein 500might be ſo lodged, here working as before, I ſhould find that,

As leo, are to the Square 76 3

So Fooo to the Square f 134. NAnd ſuch, very nears is the Number of paces required.