LETTER 30. 5 APRIL 1680 193 
In the court-yard of my house there stand two vines; 
and observing their growth to be such, that a moisture 
dripped from their shoots, I examined this sap on several 
successive occasions, just to see if I could discover any 
living creatures in it: and most times I discerned therein 
divers kinds of living animalcules, whereof one sort was 
uncommon big in comparison of the others; nay, I even 
saw some little animals that I had seen aforetime in 
divers sorts of water. Hereupon I repaired to my 
garden which lieth within this town, and there too I 
examined the sap dripping from the vines, but in it I could 
discover no living creatures, save only a little worm that 
was of an uncommon bigness,’ compared with the other 
animalcules. I betook myself thence to my garden which 
lieth without the town, and there again examined the sap 
from several vines, but could discover no living animalcules 
in it. I cut off pieces from two vine-branches, to make 
them drip the more, and went to examine the sap again 
next day, but could find therein nothing living. And 
I took a new glass phial, and caught the sap in it, and 
carried it home and examined it; but notwithstanding, 
I could perceive no living animalcules in it. I am 
now busy finding out, if ’tis possible, why there be living 
animalcules in one sap, but none in the other. 
A little later Leeuwenhoek addressed another letter on 
the same subject to Dr Gale,” and in it recorded the results 
of his further experiments and observations on the sap of vines. 
This letter is as follows: ° 
* Probably a nematode. 
* Thomas Gale (1635 ?—1702), a Doctor of Divinity, was at this time 
Secretary of the Royal Society—an office to which he was appointed in 
November, 1679. He was a Fellow of Trinity College, Cambridge, and 
Professor of Greek in the University from 1662 to 1672. Later (1697) he 
became Dean of York.—At the beginning of this letter L. says that he is 
writing to Gale because Hooke had informed him that Gale was become 
Foreign Secretary, and that he should therefore address his letters to him 
in future. 
° Letter 81. 13 May 1680. To Thomas Gale. MS.Roy.Soc. Printed 
1Ue5; 
