THREE CASTILIAN MANUSCRIPTS ON MERCANTILE ARITHMETIC AND THEIR PROBLEMS OF ALLOYS.

The aim of this work is to throw light on the existence of three Castilian manuscripts on mercantile arithmetic, all from the fourteenth century. The first, which is moreover the most general and most complete of the three, is a manuscript entitled Libro de Arismética, which is kept in the Royal Collegiate Church of San Isidoro in Leon (MS.46). It can be considered as the first book on mercantile arithmetic written in Castilian and it takes back, by some 100 years, the date which had been used up until then when speaking of treatises on mercantile arithmetic in the Peninsula. It contains an ample collection of practical examples, 192 in all. Of these, 23 (12%) are on alloys. A second manuscript is kept in the National Library in Madrid, in the Rare Manuscripts section. It is incomplete and does not have a title and it offers us a total of 76 problems. 13 (16%) of these are about alloys. The third example analysed, DeArismetica, is preserved in The Spanish Academy, Ss. 1 55, bound in a miscellaneous work entitled Escritos Diversos. We believe that it is incomplete, although it forms a coherent and perfectly intelligible whole. It omits all general aspects and, after advising us that its aim is to illustrate how to work with fractions, it begins directly with a collection of problems -48- of which only two (4%) are on alloys. [ABSTRACT FROM AUTHOR]