86 The (BjOvO1.K GF 
outfide it has various convoltions or little ribs, 
formed like crefcents, and is furrounded on 
every fide witha {trong yellow-green membrane 
or periofieum. 
I have nothing more to fay of this and 
the other creatures, as I only flightly made 
thefe particular experiments, that I might, as 
_ far as time would permit, illuftrate the hiftory 
of the covered Snail by the defcription of fome 
other kinds. I have examined into thefe things, 
that the reader, myfelf, and all mankind may 
learn to know God by his wonderful works, 
and adore and love him as the fupreme Deity 
The smethod of cutting various 
B E FORE Iconclude the hiftory of thell- 
fith, I fhall firft fubjoin a method, where- 
by fhells may be engraved and adorned with 
little pictures and figures, which is indeed a bu- 
finefs of exquifite art. Take yellow wax, and 
mix a little Venice turpentine with it, to make 
it more clammy, then add as much lamp-black 
with it as will make it very black. With this 
wax melted in a {poon, we may make any 
figures we think proper, on the furface of the 
fhell, to be carved ; then we cover thofe parts 
that are left uncovered with wax, with aqua 
fortis, which may be conveniently done by the 
help of a skewer, with a {mall piece of linen 
wrapt round it. If this be continued for a 
fhort time, all the parts of the fhell that are 
free from the wax will be eaten by the aqua- 
fortis, and in thofe places covered with wax 
will be left an higher furface. And by this 
N Av T U RIES: of, 
and the great Creator of nature. Doing this, 
we fafely purfue the fteps of Chrift, in and by. 
whom every thing we do muft be acceptable 
to God: but if we do not follow or imitate him, 
we are like thofe carelefs fervants, who buried 
in the earth the talents committed to them, ~ 
which God grant may not be our cafe; and 
may all perfons, according to their refpective 
abilities, extol and praife him; for which end I 
have communicated thefe obfervations as my 
mite, and wifh they may anfwer the intended 
purpofe. 
images and figures in foells. 
means the fhell may be adorned with various 
figures, and apartments or divifions, which ap- 
pear to be externally made thereon. But if 
after the wax is fcraped or taken off by melt- 
ing it, any corners or uneven parts fhould 
chance to remain, they muft be planed and 
perfected with the inftruments wherewith fi- 
gures are engraved. Thus three, four, or five 
eminent figures may be executed one over ano- 
ther, according to the thicknefs of the hell, 
and the places which we would have elevated, 
are firft covered with melted wax. But the 
place which the aqua fortis corrodes with its 
acrimony, ought to be wafhed with common 
rain water. Other corroding liquors are not fo 
proper for this purpofe as aqua fortis, becaufe 
they leave after them a fandy fubftance like 
chalk, which produces a roughne(s that renders 
the appearance lefs agreeable. © 
The end of the hiftory of SHELL-FISH. 
A letter from Fohn Swammerdam to the moft illuftrious Mr. Thevenot, on the 
anatomy of the Cancellus or Bernard L’ Hermite. 
ILLusTrRious SiR, 
HEN Ihad the honour of your com- 
pany for fome days in Yffi-ftreet, it 
‘often happened that fome miracles of nature 
excited us to admire the great Creator, who is 
aftonifhing in all his works. We have alfo 
debated on the fame fubje&t often, when you 
refided in Holland, and I have fhewed you 
various uncommon experiments on bees and 
other fpecies of infects. But fince the {ecrets 
of nature have, by the many inftruments and 
contrivances which I have invented, become 
clearer and more known to me; and fince I 
can in one day inveftigate what I have before 
{pent a whole week on; I can therefore now 
add a great deal to the difcoveries I formerly 
made. This you will be convinced of from 
the defcription of the internal and external parts 
of the Hermit Crab, which I firft obferved fome 
years ago at Scheveling. For, as Dr. John 
Oort, governor in Nyenrode, fent me a large 
veffel of thefe creatures, which, the better to 
preferve them for fome time, he had taken 
care to throw into {pirit of wine immediately , 
after they were caught: I cannot help giving 
you a full defcription of what I obferved in 
them, and what obligations I am under both 
to my old friend, the governor of Nyenrode, 
_who is greatly delighted with the works of 
God, and to you, illuftrious fir, who keep me 
continually employed in thefe matters, and en- 
gage and perfuade me to fearch into them. 
All mankind will admire the ftupendous ex- 
amples of the immenfe greatnefs of the won- 
derful works of God, which that f{upreme ar- 
chiteét exhibits to our contemplation in the va- 
riety of the things which he has created, that 
we may acknowledge his wifdom and infinite 
power in the works of nature, and be induced 
to love him moft ardently, and above all 
things, 
The 
