John Kersey (1616-1677) was an English mathematician. He plied his trade as a private mathematics teacher in London and acquired a high reputation both for his teaching ability and as a textbook writer. Kersey’s *The Elements of That Mathematical Art Commonly Called Algebra* was published in 1673. The volume was comprised of four “Books” and appears to be a rather complete and detailed discussion of the subject.

A portrait of the author serves as a frontispiece.

On his first page of text, Kersey introduced the "Analytick or Algebraick Art."

The reduction of algebraic fractions is discussed on page 30.

The conversion of mathematical questions into algebraic form is given due attention.

The solution of quadratic equations is discussed on page 88.

More complex situations involving quadratic equations are considered.

A problem involving Diophantine equations is introduced.

In Book IV of the *Algebra,* problems in geometry are undertaken.

*These images are supplied through the courtesy of ETH-Bibliothek Zürich and are available via e-rara.*

Index to Mathematical Treasures