shnssSaii5i 
364 EUCLID 
editions, the definitions, postulates and axioms, and the 364 
enunciations are word for word identical in Athelhard and 
Campanus. The exact relation between the two seems even 
yet not to have been sufficiently elucidated. Campanus may 
have used Athelhard’s translation and only developed the 
proofs by means of another redaction of the Arabian Euclid. 
Campanus’s translation is the clearer and more complete, 
following the Greek text more closely but still at some 
distance; the arrangement of the two is different; in Athel 
hard the ■ proofs regularly precede the enunciations, while 
Campanus follows the usual order. How far the differences 
in the proofs and the additions in each are due to the 
translators themselves or go back to Arabic originals is a 
moot question; but it seems most probable that Campanus 
stood to Athelhard somewhat in the relation of a commen 
tator, altering and improving his translation by means of 
other Arabic originals. 
The first printed editions. 
Campanus’s translation had the luck to be the first to be 
put into print. It was published at Venice by Erhard Ratdolt 
in 1482, This beautiful and very rare book was not only 
the first printed edition of Euclid, but also the first printed 
mathematical book of any importance. It has margins of 
2^ inches and in them are placed the figures of the proposi 
tions. Ratdolt says in his dedication that, at that time, 
although books by ancient and modern authors were being- 
printed every day in Venice, little or nothing mathematical 
had appeared; this fact he puts down to the difficulty involved 
by the figures, which no one had up to that time succeeded in 
printing; he adds that after much labour he had discovered 
a method by which figures could be produced as easily as 
letters. Experts do not seem even yet to be agreed as to the 
actual way in which the figures were made, whether they 
were woodcuts or whether they were made by putting together 
lines and circular arcs as letters are put together to make 
words. How eagerly the opportunity of spreading geometrical 
knowledge was seized upon is proved by the number of 
editions which followed in the next few years. Even the