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having entirely loft its diftinguiftiing brifk, fharp, fer- 
ruginous tafte, as alfo its power of ftriking a purple 
colour with galls. The elaftic fubftance contained in 
the bladder, when taken from the fire, appeared 
equal in bulk to half a pint of water. It leflened 
confiderably in the cool air, for fome days after it had 
been thus extra^fted, but did not afterwards feem to 
diminifli much in bulk, tho’ kept for a month in the 
bladdef. 
§ 2. I had feveral times occafion to reppt the 
above operation 5 and found that all the elaftic fub- 
ftance could fcarce be expelled from frefli Pouhon 
water, by the above degrees of heat, in a much 
fhorter time than that employed in the foregoing ex- 
periment. For a common quart flafk of this water, 
having been kept three hours in a water bath, heated 
to as great a degree as I could well endure with my 
hand (which might be about 130 degrees, accord- 
ing to Fahrenheit’s fcale), and having afterwards 
ftood twenty-four hours before the bladder was re- 
moved from it j when opened, was found turbid, but 
had not depofited all its earthy particles, and ftill re- 
tained a little of its briftc tafte. Another flaftc of the 
fame water, fitted in like manner with a bladder, was 
kept two hours in a fcalding heat (of about 160 or 
170 degrees of tbe fame thermometer), fo that moft: 
of its elaftic fubftance feemed forced from it ; yet, 
when the flafk was opened the next day, the water 
ftruck a purple colour with galls, and had not quite 
loft its ftiarp fubaftringent tafte ; and after about a 
third part of this water was poured out, and the reft 
fliakcn brifkly in the clofe flalk, and then fuddenly 
opened. 
