[ 664 ] 
like Mr. de Buffon and me, feen the Filaments from 
whence the fpermatic Animals fpring 5 he even calls 
them Nerves and Arteries ; and in one of his Let- 
ters to Mr. Oldenburg fays, that he faw more in 
one Minute than the moft accurate Anatomift could 
difcover by Difledion in a Day : But when he after- 
wards chang’d this Syftem, falfe as it was, of Nerves 
and Arteries for another, I believe, as falfe, that of 
pre-exifting Germs in the fpermatic Animals, he ne- 
glected to improve this Obfcrvation as he might 
have done 5 nay he afterwards took no farther No- 
tice of it, but barely to fay, that it was to be ne- 
glected. This Remark I had from Mr. de Buff on. 
Thc.Difference therefore betwixt Mr. Lewenhoeck 
and Dr. Harvey was, that the firft had an Hypothecs 
to maintain, and the latter nothing in View but to 
follow Nature, without trufting too much to the 
firft P htfnomena, as I hope I fhall appear to have 
done in this my Enquiry. 
I had almoft forget one Remark that coincides 
with my Syftcm 5 that although animal and vegetable 
Subftances by a chymical Analyfis appear to differ, 
they are neverthelefs found by a natural Corruption 
to be reducible to the fame Principles. This has 
been obferved long ago by many Naturalifts. 
And now I think I have nothing more to add, 
only that I would be undeiftood, when I fpeak of 
a productive Force in Nature, &c. to mean only a 
Force, which, tho’ modelfd by the Supreme Cre- 
ator, goes no further than the mechanical and ma- 
terial Parts of a Man. I well know that we are com- 
pofed of two very different Principles j and no 
one mere philofophical Truth whatfoever prefents 
* itfelf 
