Cji8) 
der the life of it fafe and beneficial. Of the number of thefe 
feems to be that French Vli tnok , Gafper de Gurye de Montfolj ^ 
who in a late Letter o{ his to Monfieur Bourdelot^ declares to the 
Woiidjthat this is a very Ingenious Invention^and fuch an one, as 
mayprove very ufeful-, butwithail^ that, in his opinion, it is to 
be ufed with much caution, as not being like to be pradifed 
innoxioufly, if imprudent men do mannage it, and the con- 
courfe of two differing forts of Blood requiring many tryals, and 
a careful observation of many circumftances^ to give affurance. 
He fuppofes , that the Blood of every Animal is endowed with 
its peculiar Temper, and contains in the Aggregate of its parts, 
different natures, principles, figures, and even a different Centre.- 
Whence he concludes^ that two Subflances thus difTering, and ' 
containing plenty of Spirits ^ are not reducible to one and the 
fame Centre, nor to one and the fame Body without Fermenta- 
tion^j and that this Operation may prove of danger to him, that 
fhall have admitted into his Veins a ftrange Blood ( wont to 
be free in its native vefTels ) without pafTing through thofe 
degrees , that muft give it Impreflions futable to the temper 
and FunSiions of the Vitals of the Recipient. And taking 
for granted , that no confiderat man will hazard a Total Trans- 
fufion, he acknowledges that a Partial one may be infome ca- 
fe and ficknefTes very ufeful , provided, it be prailifed circum- 
fpedlly , upon a Body yet ftrong enough , and in a moderate 
quantity fo as the Spirits and Blood of the Recif ient may be 
able to difTolve and mafler the transfufed ftrange Blood, and 
convert the fame into its own nature by a g^ntk FMition -j to . 
obtain by fuch a commixture a principle of motion, that may 
caufe a better habit of Body. And he believes, that this E- 
bullition muft alwayes happen in Bloods of differing parts and 
qualities and that very hardly two Anitnals, of differing fpe- . 
xies's, nges and tempers^ will be met with, that have Blood fo 
irke one another, as not to need Fermentation) to make a requi- 
fit m.ixtnre. He doubts not^ that if a fubftance could be found 
fo refembling that of our Spirits,, as that it would immediate- 
ly unite itfelf with them, not needing any alteration, the ^ 
Transfufion of fuch a Subftance would be capable to produce 
tffeds little lels than miyaGulous ^ by relieving the proftrated 
' ' ^ forces 
