Liquefaction and S 2 of Carbonic Acid. 353 
_ At about —110° liquid s s acid is frozen, and the ice 
sinks i in its own liquid, and at —130° alcohol of .798, assumes a 
viscid and oily appearance, which by increase of cold, is augmen- 
ted until at —1 46° it is ike melted wax. Alcohol of .820- froze 
readily. : 
~ At —146° sulphuric sihehi is not in the slightest degree altered, 
When a piece of solid carbonic acid is pressed against a living 
animal surface, it drives off the cireulating fluids and produces” 
a ghastly white spot. If held for 15 seconds it raises a blister, 
and if the application be continued for 2 minutes a deep white 
‘depression with an elevated margin is perceived ; the part is killed, 
and a slough is in time the consequence. I have thus produced 
both blisters and-sloughs, by means nearly as prompt as fire, but 
much less alarming to my patients. 
The specific gravity of liquid carbonic acid may be estimated 
either by weighing a given measure of it in a tube, and deduct- 
ing the weight of the tube, and of a superincumbent gas, or by 
means of very minute bulbs of glass as suggested by Sir M. Far- 
aday. By the latter means I obtained the setae. maeults, 
Which 2 are ya arp with those of Thilorier.. 
: Thilorier. 
’ Temp. Fahr. r Sp. Gr. 4 ee Fahr. Sp. Gr. 
BIO ere COM ge SBOP “pe! ye 
es MOOD ee a UNE 5 ty ee oe Be 
OO dae oo NOG Ba ee aces ey 
GA° 2. he 5 OBB, RE ae a A 
_ 6°... & - 86° - .60 
The specific gravity particularly at 32°, was examined repeat- 
edly, and with different bulbs, and always found to be at, or very 
near, to .93. The difference never amounted to .005. "The sp. 
gr. as given by Thilorier at 32° is 83. The anomalous expansion — 
of the liquid as indicated by both ‘sets of experiments is truly sur- 
ptising. By mine 73.85 parts raised from 32° to 74°, or 42°, -be- 
come 93 parts, and gain 19.15 parts, while the same bulk of the 
gases acquires in the same range of temperature only 6.46 parts, or 
the liquid is expanded very nearly three times as much as its own 
orany other gas. According to Thilorier, 60 parts gain 23 parts 
by an elevation of 54°, while the same bulk-of air would under 
_ like cireumstances be supuiontid only by 6.75 parts ; or the _ 
is nearly four tinies as expansive as the gases. 
POPE RER NR’: 45; 
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