INTRODUCTION XiX

'"Torre who had devoted his life to astronomy, but had not com—
pleted a treatise, on his deathbed begged Fracastorius to use
his material.'  Fracastorius describes, in & Preface, this moving
scene, and says he will "explain all astronomy'' by della Torre's
theory.  He says, to the Pope: ^If you want to reform the
calendar, this may help you'^; but I cannot find that the trea—
tise aroused much interest, though it had some critics.? Mas—
salongo, whose lecture on Fracastorius is, throughout, a panegy—
ric, says that Homocentrica prepared the way for Copernicus,
but Dreyers calls it 'a failure, a belated attempt to revive the
theories of Eudoxus and Callippus, and nobody has ever thought
it worth while to make a thorough study of the book". How—
ever, Giordano Bruno (1550—1600) seems to have read it, and.
paid Fraeastorius the high compliment of making him one of
the interlocutors in his Dialogues, On (he Infinile Un^iverse.
Fracastorius had long been safe from the Holy Office in the
grave; his orthodoxy, or caution, was such that he would cer—
tainly have resented his appearance in such heretical company.*
On the strength of a passage in JH/omocenfrica, some biogra—

 

1534, and meant to dedicate it to Giberti, but his patron advised
him to dedicate it to ^*Vou who hold the keys and dominion of the
sky and stars'. Barbarani regards this advice as sardonic and as
a sign that Giberti knew that Fracastorius had transferred his
homage, but it seems, rather, a friendly caution. For it was not
safe to commit oneself to any astronomical theory, or in fact to any
theory, except under the shelter of the highest clerics. So in 1543
Copernicus, urged by his friends, dedicated his famous treatise De
Rtevolutionibus Coelesttum, to this same Pope.

: For a discussion as to the actual contribution of della Torre,
see Barbarani's Ijfe, ed. of 1897, p.235. In his opinion, the trea—
äse embodies Fracastorius' own researches, and owes little to della,

orre.

2Sabazio was the most important of these, and Fracastorius
answered his objections in an appendix.

sHistory of Planetary Systems, Cambridge, 19060. For &a more
sympathetic treatment of JHomocenfrica see C. and D. Singer,
The Scientific Position, of Girolamo Fracastoro, in Annals of Medicalt
History, Vol I. No. I. 1917. Here is given an account of his dis—
cussion of the refraction of light, and the magnifying effect of a&
deep medium such as water, and they state that it is probable that
the first orrery (model of the movements of the planets) was con—
structed by Fracastorius. Burton, Anaiomy of Melancholy, had
ïe.acll( ,I,Iomocentrica, and says, '^Fracastorius makes 72 Homocen—

ricks!.

4 For these Dialogues, see below, p. lii.