**Wallis**

(1) Born at Ashford, Kent, November 23, 1616; died at Oxford, October 28, 1703.

(2) According to the *Dict. Nat. Biog.* Older authorities give 1654.

(3)*Arithemetica Infinitorum, sive Nova Methodus Inquirendi in Curvilineorum Quadraturam, aliaque difficiliora Matheseos Problemata*, Oxford, 1655.

(4) The Latin edition is in volume II of his *Opera Mathematica*, Oxford, 1693-1695.

(5) D.E. Smith, in the *Bulletin of the Amer. Math. Soc.*, XXIV (2), p. 82.

(6) See his *Opera Mathematica*, I, 441, where he explains that he uses a small square for a symbol for the ratio of the square on the diameter to the area of the circle. In our symbolism this is 4(r^2): pi(r^2 ), or 4: pi. On page 469 he gives the value stated above. See also his Volume II, cap. lxxiv.