165

GENERAL U S E

OF THE

C ANON.

AND

er.

Tables of LoOGARITHMs.

Okarithmetick is a Logical kind of Arithmetick, or arti-a ſcial ule of Numbers invented for the eaſe of the Cal-e culation, wherein each Number is fitted witlr an Arti-e laeial, and theſe Artiffeial Numbers ſo ordered, thatwhat is produced by Multiplication of natural Num-

4. bers, the ſame may be effected by the Addition of theſetheir Artiffeial Numbers; what they perform by Diviſien, che ſame ishere done by Subtraction: and ſo the hardeſt part of Calculation arei-ded by an caſie Proſthaphæreſis. i

All rhis ſhall be made plain by apply ing that to cheſe Artificial Num-bers, which J have ſet down before, for the uſe of my Lines of Num-bers, Sines and Tangents in the Uſe of the Sector and Croſs“ Staff.Wherein che Reader is to obſerve, that what is to be wrought by roundNumbers only, is beſt done by Mr. Brigges his Logarithms, but cherAſtronomical part concerning Arks and Angles, by my Canon ef Artificial Sines and Tangents. 5: f

Q HAN.