86 LEEUWENHOEK AND HIS ‘“‘ LITTLE ANIMALS ”’ 
in a well set-up body, must so contract, that how little 
food soever be in it, ’tis ever full. 
The stomach being now overladen with food, and 
unable to get rid of it because the gut is full of chyle; 
and these long strainings of the stomach being against 
its natural shape: it arouses, by its strivings, a pain in 
the midriff (which they call the Diafragma), which is 
thereby hindered in its continual motion; which also 
stirs up a second pain. The midriff accordingly presseth 
on the lung; and thereby, the lung is prevented from 
performing its office. And this being so, there must 
follow a great tightness and a great vomiting: and such 
violence is done to the body, to the stomach as well as to 
the guts, that the chyle in the gut is thereby pushed 
onwards; so that there followeth a motion in the gut 
itself. And, as I imagine, when the gut is full up, the 
gall-bladder can’t empty its bile into the gut, yet with 
these onpushings of the chyle it pours a great quantity 
of bile into the guts; therefore on the day when this 
happens, four or five stools are brought off, whereas on 
the other days there ensueth a constipation. 
You have here the feeble notions I’ve hammered out 
of my last distemper. Pray take it not amiss that I take 
upon myself to argufy about it. 
The foregoing lines are not only an interesting record of 
Leeuwenhoek’s bodily condition in his 84th year, but also a 
typical example of his own particular system of physiology. 
References to his age and his infirmities become more 
numerous with advancing years. He continues to make and 
record observations and speculations, and to promise more: 
but he often begs the Royal Society to make allowance for his 
senescence, and sometimes qualifies his promises with expres- 
sions such as “if my health permits”.' At the end of 1717 
Leeuwenhoek thought his own end was near; and he therefore 
inscribed a “last letter” to the Society, as an envoy to the 
* met gesondheijt, ete. 
