IX. The ConflruBion and properties of a new Quadra* 
trix to the [Hyperbola, By Mr . . . Perks. Com* 
muriicated by Mr Abr. de Moivre, t. Of S. 
T He Circle, Ellipjis and Hjkrbola being not Geome- 
trically Quadrable ( as infinite others ) there have 
been two ways made ufe of to find their Areas, r. By 
Converging Series, whereby Approaches are made nearer 
and nearer, according to the exa&nefs defir’d. 2. By 
Quadratices, that is. Mechanical Curves, which determine 
the Length of certain Lines, whofe Squares or Reftangies 
give the Area of the Figure defir’d. Of this fort is the 
old Qjiadratrix of Dinojlrattts, by which the Circle and 
Ellipfe are fquared $ and another fort (for the fame pur- 
pofe ) I inferred in the Tranfaffions about 5 years ago. 
Since that, having found the Conftru&ion of a Curve, 
from whence (befides its own Quadrature and ReSificatmf) 
the Quadrature of the Hyperbola is deriv’d, I thought the 
following Account might not (to feme) be unaccepta- 
ble. 
Let AB, C D, be two ftraight Rulars joyned at B, and 
there making a right Angle. (Their length according to 
the largenefs of the Figure you will deferibe.) E F is ano- 
ther Rular fomewhat longer than A B. Near the one end E, 
let a little Truckle-wheel ( reprefented edge- wife by g h. and 
made of a thin Plate of Brafs or Iron ) be fanned to 
the Rular by a Pin ( i, ) chorow its Center, fo that 
the Wheel may turn about upon the Pin ( i ) tight to 
the Rular without joggling. 
13 X 
On 
