252 LEEUWENHOEK AND HIS ‘“‘ LITTLE ANIMALS” 
It must be confessed that the foregoing observations add 
little to those made previously. But bacilli, spirochaetes, and 
Leptothrix are again recognizably described—if not recogniz- 
ably figured: and this letter therefore confirms, to some 
extent, the earlier one (No. 39). It also gives us a characteristic 
glimpse of the author and his methods, and for that reason— 
if for no other—deserves notice. 
Various writers have already reproduced the illustrations 
accompanying this letter, but nobody hitherto appears to have 
made any attempt to interpret them—apart from noting that 
they represent “ bacteria”. This is to be explained, I think, 
in the usual way : most people merely glance at Leeuwenhoek’s 
figures and do not take the trouble to read his words relating 
to them, so that his excellent observations have been all too 
often misunderstood or treated as mere curiosities.’ 
A few further observations on the bacteria about the teeth 
were interpolated in a letter written to the Royal Society 
five years later. In the midst of a discussion of the eggs of 
snails, the germination of wheat, and the spat of oysters, we 
find the following digression :” 
I can't forbear to tell you also,’ most noble Sirs, that 
one of the back teeth in my mouth got loose again, and 
bothered me much in eating: so I decided to press it 
hard on the side with my thumb, with the idea of making 
the roots start out of the gum, so as to get rid of the 
Tn passing, I may also add that a recent writer (Prescott, 1930) cites 
the foregoing letter (No. 75) as evidence that “ A. von Leeuwenhoek ”’ held 
the view “that microscopic organisms were produced spontaneously from 
non-living matter.” It is difficult to conceive how anybody who has ever 
read a word of L.’s writings could make such a mistake: but perhaps 
Prescott—like many another writer who quotes L.—did not consult the 
work to which he refers. This would also explain the singular fact that he 
cites the original Latin edition of the letter (1695) but gives the pagination 
of the editio novissima (1722). 
2 From Letter 110. 10 September 1697. To the Royal Society. 
MS.Roy.Soc. Printed in Brieven, Vol. III (Sevende Vervolg, 1702); Opera 
Omnia, Vol. III (Epist. Soc. Reg., 1719); and in abbreviated English in 
Phil. Trans. (1697), Vol. XIX, No. 235, p. 790. The passage here 
translated begins on p.40 of the Dutch edition, p.35 of the Latin, and 
p. 797 of the Phil. Trans. 
° ook printed version: not in MS. 
