A UNIQUE COLLECTION OF ARITHMETICS 231 



cussion of arithmetic. Finger reckoning and a number game called 

 Eithmomachia are other related subjects which received elaborate treat- 

 ment. The first modern encyclopedia to appear in print is the 

 "Epitome of all Philosophy" by the Carthusian monk Gregorius Reisch, 

 the publication appearing in Strassburg in 1503. " Pythagoras " and 

 " Boethius " adorn the first page of the part devoted to arithmetic. 



It would appear that scientists have, in the course of centuries, 

 grown more modest in their published claims. Borghi's " Noble work 

 of arithmetic treating all those things which are requisite for mer- 

 chants " sounds like a boast. More seductive are " The Ground of 

 Artes," " The Castle of Knowledge/' " The Pathway of Knowledge " 

 and " The Whetstone of Witte," mathematical works by Robert 

 Recorde, the royal physician to Edward VI. and Queen Mary. Recorde 

 was the first to use the present equality sign, stating that no two things 

 can be more equal than two such lines. His were the most influential 

 English mathematical publications of the sixteenth century. Equally 

 enticing as the titles of Recorde was Humphrey Baker's " The Well 

 spring of Sciences, Which teacheth the perfect work and practise of 

 Arithmetick, both in whole Numbers and Fractions" (London, 1562). 



The most fitting name with which to terminate a discussion of the 

 printed arithmetics of the sixteenth century is that of Adam Riese. 

 So- widely were his books used and so deep the impression which they 

 made that even to-day, nearly four centuries after he wrote, the expres- 

 sion to reckon " nach Adam Riese " is common in Germany. Riese's 

 works quite supplanted the numerous editions of the Rechenbuch by the 

 versatile Jakob Kobel, who was Reichenmeister, printer, engraver, wood- 

 carver, public official, as well as a successful text-book writer. Kobel's 

 " Rechenbuch " of 1514 bears silent but eloquent testimony to the 

 tremendous inertia that must be overcome by any new system that 

 revolutionizes the common processes of thought. Kobel's arithmetic, 

 four hundred years after the Hindu- Arabic numerals had been explained 

 in Europe, is wholly in Roman numerals, even to the fractions. Riese's 

 work made the publication of any other arithmetic in Roman numerals 

 impossible. 



Part II. of the " Rara Arithmetica " treats of the rich collection of 

 mathematical manuscripts in the Plimpton library. The oldest of these 

 is a beautifully written Latin Euclid (about a.d. 1260). This manu- 

 script appears to be the copy given by the translator Campanus to 

 Jacques Pantaleon when he was Patriarch of Jerusalem. Campanus 

 was chaplain to Pantaleon both in Jerusalem and later when that 

 churchman became Pope Urban IV. 



An arithmetic written about 1339 by Paolo Dagomari, also known 

 as Paul of the Abacus, furnishes the clue to the derivation of our per 

 cent, symbol. The sign is derived from the abbreviation c° for cento 



