Liquefaction and Solidification of Carbonic Acid, 353 



At about — 110° liquid sulphurous acid is frozen, and the ice 

 sinks 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 — 146° it is like melted wax. Alcohol of .820 froze 

 readily. 



At — 146° sulphuric ether is not in the slightest degree altered. 



When a piece of solid carbonic acid is pressed against a living 

 animal surface, it drives oiF the circulating 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 perceivedr^; 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 following results, 

 which are compared with those of Thilorier. 



Thilorier. 

 Temp. Falir. Sp. Gr. 



32° - .83 



- 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- 

 prising. 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 af 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 

 or any other gas. According to Thilorier, 60 parts gain 23 parts 

 by an elevation of 54°, while the same bulk of air Avould under 

 like circumstances be augmented only by 6.75 parts ; or the liquid 

 is nearly four times as expansive as the gases. 



Vol. XXXV.— No. 2. 45 



