By CORROSION. 353 
injected veffels without breaking them down by the force 
applied in cleanfing them. 
The following directions will ferve to guide the opera- 
tor in thefe different manceuvres. 
The common injections are compofed of wax and fuet, 
or of wax and oil; the fuet or oil is made ufe of to foften 
the wax, and to give it the neceflary confiftence. We 
cannot employ fuch a compofition in our corroded prepa- 
rations, being oppofed to the third principle laid down; 
becaufe the menftruum we ufe for deftroying the parts that 
furround the veffels, will alfo attack and confume the fat 
and animal fubftances which enter into the compofition of 
the inje&tion. But we may employ the following compo- 
fitions, the goodnefs whereof has been proved by repeated 
trials, viz. 
First RECEIPT. 
Take of white or the beft yellow wax and purified rofin 
each equal parts, e. g. ten or twelve ounces; melt them to- 
gether and add a fufficient quantity of {pirit of turpentine, 
to give a due confiftence, that is from fix to eight ounces. 
It isadvifeable to melt the rofin firft, and ftrain it through 
a piece of fine linen; becaufe, in the ftate it is bought out 
of the fhops, it is often mixed with foreign fubftances. 
I am of opinion this injection will turn out to be finer 
than the following, that is, it will penetrate into ftill 
f{maller veffels, but it is thought to have the inconvenience 
of being more brittle; fo that after corrofion, the moft 
flender of the veffels are more liable to break down in 
handling the preparation. 
The following is the receipt which the celebrated Mefirs 
Hunter of London, have commonly made ule of. It is 
lefs brittle and produces a firmer cohefion of parts, with 
nearly the fame confiftence as the former. Belides, it en- 
ters very fufficiently into the capillary veflels. 
SECOND RECEIPT. 
Take of pure rofin eight ounces, of wax four ounces, 
of Venice turpentine a fufficient quantity, that is, about 
bb eleven 
