316 Intelligence and Miscellaneous Articles. 



operation of determining the density of its vapour ; the matras after 

 the operation retained the peculiar odour of this chlorinated methylic 

 oil. It is almost impossible to get rid of the last traces of it : it 

 resists the action of concentrated sulphuric acid, even when the 

 chloroform is long exposed to it. 



There do not, then, exist two chloroforms ; the cause of the ap- 

 parent difference is the presence of the peculiar oil produced by the 

 reaction of chloride of lime on pyroxylic spirit. 



This fact being established, search was instituted to determine 

 whether, during the preparation of chloroform from alcohol, an 

 analogous substance was formed. Experiment confirmed suspicion ; 

 the rough chloroform was washed first with water and afterwards 

 with carbonate of soda ; it was long kept in contact with chloride 

 of calcium to combine with the water ; lastly, it was filtered and 

 distilled in a water-bath from a glass retort. There remained in the 

 retort a liquid aromatic substance, but of an odour very different 

 from that of chloroform ; the proportion was very small, for not 

 more than 40 grammes were obtained from 20 kilogrammes of chlo- 

 roform. 



This oil differs essentially from that obtained from chloroform 

 prepared from pyroxylic spirit. It is more dense than water, has a 

 peculiar acrid and penetrating odour, not at all resembling that of 

 the other oil ; but like it, it was found to be a mixture of different 

 compounds; for the thermometer, which on heating was 134° F. 

 at the commencement of ebullition, became as high as 242° F. ; and 

 the temperature would undoubtedly have been increased if the ex- 

 periment could have been tried with a larger quantity. All these 

 compounds are chlorinated, as proved by examining the results of 

 their combustion. 



It results from the preceding statements, that as chloroform ob- 

 tained from pyroxylic spirit cannot be entirely deprived of its pyro- 

 genous odour, it ought not to be employed for inhaling. The pre- 

 sence of chlorinated oil, in the small quantity even in which it exists 

 in chloroform obtained with alcohol, has a strongly-marked influence 

 in its employment : it is to it that must be attributed the uneasiness, 

 nausea and vomiting, occasioned by inhaling chloroform. 



It follows that it is absolutely necessary to rectify chloroform by 

 distillation in order to separate the foreign body which it contains, 

 and moreover the distillation should be stopped sufficiently soon. 



In concluding, the authors remark that chloroform, like hydro- 

 cyanic acid, when poured on filtering paper, partly evaporates so 

 rapidly as to occasion sufficient cold to solidify the remainder in 

 white silky tufts, which remain for a few seconds. 



The authors conclude from the facts above stated, that — 



1st. Chloroform prepared from pyroxylic spirit is identical with 

 chloroform properly so called. 



2nd. The purification of methylic chloroform is too difficult to 

 admit of its advantageous substitution for normal chloroform. 



3rd. During the preparation of chloroform there is always pro- 



