296 ANNUAL OF SCIENTIFIC DISCOYERY. 



the narcotized condition, the vessels do not contract, but under 

 the influence of ether, in the hiter stages, before death occurs, di- 

 lation and regurgitation are observed. The hitter is noticed also 

 when chloride of methvlene is used. With both reagents breath- 

 ing and vessel circulation cease before the heart's action. He 

 concluded that anaesthetic vapors act directly upon nerve matter, 

 either by preventing the development of force or by stopping con- 

 duction. The latter hypothesis is supported by the fact, proved by 

 experiment, that these vapors obstruct the conduction of heat and 

 electricity. — Med. limes and Gaz. 



NEW ANAESTHETIC BICHLORIDE OF METHYLENE. 



Dr. B. W. Richardson has recently discovered a new general 

 anaesthetic, which he described and exhibited before the British 

 Association. The general chemistry of the monocarbon series to 

 which this new agent, the bichloride of methylene, belongs, has 

 been given under " Chemistry," on pages 190, 191 of this volume. 



The formula of this fluid is CH2 CI2. It has an odor as sweet as 

 that of chloroform, but boils at 88° F., 64:° less than the boiling- 

 point of the latter. It rapidly and easily narcotizes animals to 

 perfect anaesthesia, causing scarcely any excitement, and with 

 perfect recovery ; it seems to combine the properties of chloroform 

 and ether, but is more readily administered and with more perma- 

 nent eff'ects than either. 



The chloride of methyl, a certain and gentle anaesthetic, exists 

 at ordinary temperatures as a permanent gas. It is very soluble 

 in ether, and the saturated compound is one of the most perfect 

 of anaesthetics ; though not very stable, it probably has no supe- 

 rior in the evenness of its action, and in the rapidly produced, pro- 

 found, and prolonged sleep. Water will take up four volumes of 

 it, and forms a powerful intoxicating drink, palatable with a little 

 sugar, of a very transitory eft'ect. Introduced into the stomach 

 as a soothing and refrigerating drink, and as an anaesthetic for 

 slight operations, it promises to be a useful remedial agent. 



Bichloride of methylene is a colorless fluid, more volatile than 

 chloroform, the vapor being three times heavier than air, so that 

 it requires more free administration than chloroform, but less in 

 quantity than ether. Chloroform vapor will not support combus- 

 tion, stopping oxidation without undergoing decomposition ; the 

 vapor of bichloride of methylene supports combustion with a 

 brilliant flame, forming carbonic and hydrochloric acids. This 

 proves that Dr. Snow's theory, that the action of anaesthetics is to 

 arrest combustion in the blood, is not true. 



The bichloride of methylene mixes readily with ether, and the 

 two fluids have, within four degrees, the same boiling-point, so that 

 the mixture vaporizes evenly and equally ; the difference in the 

 specific gravities of the two vapors is the only objection to the 

 combination. The bichloride also combines with chloroform in all 

 proportions. It should always have a neutral reaction to test- 

 paper, and, to 2>revcnt decomposition, should be kept from the 



