Secondary Literature. What littleinformation there is on Hérigone has been collected by B. Boncompagni in Bullettino di bihliografia e di storia delte scienze matematiche e fisiche, 2(1869), 472–476; and P. Tannery in Mémoires scientifiques, X (Paris, 1930), 287–289. The controversy with Morin is described by J. E. Montucla in Histoire des mathématiques, 2nd ed., IV (Paris, 1802), 543–545. A list of Hérigone’s mathematical symbols is given by F. Cajori in History of Mathematical Notations, I (Chicago, 1928), 200–204, passim.

Original Works. Hérigone’s only important published workis Cursus maihenmaticus nova, brevi el clara methodo demonstratus, 6 vols. (Paris, 1634–1642). There are three other “editions” of the Cursus(1643, 1644), but these consist of nothing but sheets from the original ed. with a few deletions and additions, and new title pages. Hérigone also published a paraphrase of the first six books of Euclid (1639), but it consists of little more than the French portion of vol. I of the Cursus; there is also a spurious 2nd ed. (1644).

He also introduced a code by which numbers were translated into words to aid memorising them. The code was as follows: 1=p,a;2=b,e;3=c,i;4=d,o;5=t,u;6=f,ar,ra;7=g,er,re;8=l,ir,ri;9=m,or,ro;0=n,ur,ru1 = p, a; 2 = b, e; 3 = c, i; 4 = d, o; 5 = t, u; 6 = f, ar, ra; 7 = g, er, re; 8 = l, ir, ri; 9 = m, or, ro; 0 = n, ur, ru1=p,a;2=b,e;3=c,i;4=d,o;5=t,u;6=f,ar,ra;7=g,er,re;8=l,ir,ri;9=m,or,ro;0=n,ur,ru. So to remember a number such as 314159 one produced a word such as 'cadator' which then translated back into 314159. The assumption here was that 'cadator' was easier to remember than 314159.

Although the art of mnemonics goes back to ancient Greece (theterm comes fromMnemosyne, the Greek goddess of memory), it wasnot until 1634 that a Frenchman named Pierre Hrigone published inParis hisCursus Mathematici,which contained an ingenious systemfor memorizing numbers.