The LIFE of JOHN SWAMMERDAM. XV 
becaufe they diffe&ed them equably ; whereas knives and lancets, let them 
be ever fo fine and fharp, are apt to diforder delicate fubftances, as in 
going through them they generally draw after them, and difplace, fome 
of the filaments: his knives, lancets, and ftyles were fo very fine, that 
he could not fee to fharpen them without the afliftance of the micro- 
{cope; but with them he could diffe& the inteftines of Bees with the 
fame accuracy and diftinétnefs, that others do thofe of large animals. He 
was particularly dextrous in the management of fmall tubes of glafs no 
- thicker than a briftle, drawn to a very fine point at one end, but 
thicker at the other. Thefe he made ufe of whenever he had a mind 
to fhew, and blow up the fmalleft veffels difcovered by the microfcope; 
to trace, diftinguifh, and feparate their courfes and communications, or 
to inject them with very fubtil coloured liquors. As to the infeés them- 
felves, he ufed to fuffocate them in alcohol or fpirit of wine, in water, 
or fpirit of turpentine, and likewife preferved them for fome time in 
.thefe liquids, by which means he kept the parts from putrefying, and 
confequently collapfing and mixing together; and added to them, befides, 
fuch ftrength and firmnefs, as could not fail of making the difleGions 
far more eafy and agreeable. When he had divided tranfverfely with 
his fine fciffors the little creature he intended to examine, and had care- 
fully noted every thing that appeared without further diflection, he pro- 
ceeded to extract the vifcera in a very cautious leifurely manner, with 
other inftruments of equal fubtility; but firft took care to wafh away 
and feparate with very fine pencils the fat with which infects are moft 
plentifully fupplied, and which always occafions fome damage to the 
internal parts, before they can be extraéted. This laft. operation is beft 
performed upon infeés whilft in the Nymph ftate. Sometimes he put 
into water the delicate vifcera of the infe@ts he had fuffocated, and then 
fhaking them gently, procured himfelf an opportunity of examining them, 
efpecially the air veflels, which by this means he could feparate from all 
the other parts whole and entire, to the great admiration of all thofe who 
beheld them ; as thefe veffels are not to be diftin@ly feen in any other 
manner, or indeed feen at all without damaging them. He often made 
ufe of water injected by a fyringe, to cleanfe thoroughly the internal 
parts of his infects, then blew them up with air and dried them; by which 
means he rendered them durable, and fit for examination, at a proper 
opportunity. Sometimes he has examined with the greateft fuccefs, and 
made the moft important difcoveries in infe@s that he had preferved in 
balfam, and kept for years together in that condition. Again, he has fre- 
quently made punctures with a fine needle in other infets, and after 
{queezing out all their moifture through the holes made in this manner, 
filled them with air by means of very flender glafs tubes, then ‘dried them 
in the fhade, and laft of all anointed them with oil of {pike, in which 
a little refin had been diffolved, by, which means they retain their proper 
forms for a very long time. He had fo fingular a fecret for preferving the 
very nerves of infeéts, that they ufed to continue as limber and as per- 
{picuous as ever they had been. As to Worms in particular, his way was 
to make a fmall punéure or incifion in them towards the tail, and after 
having very gently, and with great patience {queezed out all their humours, 
and great part of their vifcera, inject them with wax, fo as to give and 
continue to them all the appearances of living, healthy, and vigorous 
creatures. He difcovered that the fat of all infe@s was perfectly diffolvible 
. in 
