104 
LEEUWENHOEK AND HIS ‘‘ LITTLE ANIMALS ”’ 
It were endless .... to give any Account of Mr. 
Leeuwenhoek's Discoveries ; they are so numerous as to 
make up a considerable Part of the Philosophical Trans- 
actions, and when collected together, to fill four pretty 
large Volumes in Quarto, which have been publish’d by 
him at several Times: And of such Consequence, as to 
have opened entirely new Scenes in some Parts of 
Natural Philosophy, as we are all sensible, in that famous 
Discovery of the Animalcula in Semine Masculino,' which 
has given a perfectly new Turn to the Theory of 
Generation, in almost all the Authors that have since 
wrote upon that Subject. 
But however excellent these Glasses may be jude’d, 
Mr. Leeuwenhoek’s Discoveries are not entirely to be 
imputed to their Goodness only: His own great 
Judgment, and Experience in the Manner of using 
them, together with the continual Application he gave 
to that Business, and the indefatigable Industry with , 
which he contemplated often and long upon the same 
Subject, viewing it under many and different Circum- 
stances, cannot but have enabled him to form better 
Judgments of the Nature of his Objects, and see farther 
into their Constitution, than it can be imagined any 
other Person can do, that neither has the Experience, 
nor has taken the Pains this curious Author had so long 
done. 
Nor ought we to forget a Piece of Skill, in which he 
very particularly excell’d, which was that of preparing 
his Objects in the best Manner, to be view’d by the 
Microscope; and of this I am perswaded, any one will be 
* The discovery was announced in a letter written to the Royal Society 
in November 1677—at the very moment when the marriage of William and 
Mary was being celebrated in London. 
2 
Some further particulars of the microscopes themselves follow here: 
ef. p. 317 wnfra. 
