202 Half-Hours with the Old Naturalists. [April, 
In 1669 he wrote the larger part of his great history of 
inserts, which, however, he did not at once publish. He 
had got together upwards of 3000 species of inserts, — a large 
collection for the seventeenth century, — and had examined 
them with a care and an accuracy which hitherto had 
had no parallel. He had dissected most of the species, 
traced their development from the larva — or whenever pos- 
sible from the egg — to the mature form, and had refuted the 
fabulous notion, handed down from the days of classical 
antiquity, that they are or may be generated from putrescent 
matter. He laid the foundations of the anatomy of inseCts. 
He devised a kind of dissecting microscope, and introduced 
the use of scissors for delicate operations, as being less liable 
to tear thetissues than knives. He injected coloured fluids, in 
order to render the different parts more distinct and to show 
their connection. For this purpose he employed minute 
glass tubes. He had not, of course, at his command the 
high magnifying powers of the modern microscopist, nor 
the polarising apparatus, but the general accuracy of his 
descriptions and his drawings has often excited the surprise 
and admiration of modern observers. 
In the course of the year 1669 he encountered a new and 
very serious trouble, which continued almost to the end of 
his life. The elder Swammerdam would rather have seen 
his son a routine practitioner, writing out prescriptions and 
pocketing fees, than a brilliant discoverer. Hence a quarrel 
resulted. The old apothecary threatened to stop his son’s 
allowance if he did not immediately give up his researches 
and devote himself to practice. By way of appeasing his 
father he undertook to clean, re-arrange, and catalogue the 
family museum, — a laborious task, for which a man of much 
inferior abilities would have been amply sufficient, and which 
to him was both waste of time and weariness. He was, 
however, physically unequal to the fatigues of medical 
practice. 
In 1670 he had another attack of illness, and was forced 
to retire into the country for change of air and rest. His 
rest, however, consisted in completing his treatise on the 
Ephemera, which was not published until the year 1675. 
The following year he sent his plates of the anatomy of the 
human uterus, which had been drawn in 1667, to the Royal 
Society, accompanied by a series of injected preparations 
and a full account of his methods. 
So far we have seen him bravely struggling on amidst all 
the difficulties of failing health, scanty means, and family 
discord, yet sustained by the pure love of truth. But a sad 
