Reaction of Sulphuric Add. 249 



phnr modified by an atom of organic matter which does not, as 

 in the first class, act as a base, or diminish the saturating power 

 of the acid. If, therefore, we should adopt the nomenclature of 

 the German chemists, with the' change of sulphuric into hypo- 

 sulphuric as necessary to designate with precision the acid of sul- 

 phur in question, for the acids of the second class, calling them 

 benzohyposulphuric and napthalohyposulphuric ; and applying 

 the same idea to the acid described in this article, name it hem- 

 lohyposulphuric, the ends to be attained in forming a nomen- 

 clature would perhaps be as well answered, as is practicable with- 

 out departing too widely from established custom. 



Hemlosulphuric acid possesses a sour taste and peculiar odor. 

 It does not appear susceptible of crystallization, either when free 

 or as far as I have examined its compounds, when combined with 

 bases. The salts which it forms with potash lime and barytes 

 leave in the mouth a decided and long continued impression of 

 sweetness. Though extremely soluble they are not dehquescent. 

 If the hemlosulphate of barytes be kept for a length of time at a 

 temperature between 500^ and 600°, the sulphate of barytes 

 and organic matter of which it is composed separate, the latter in 

 the shape of a resinous powder insoluble in water, though soluble 

 in alcohol and ether. This seems a singular instance of a body 

 very soluble in water, affording by the mere separation of its con- 

 stituents, two others eminently insoluble in that liquid. 



In the resinous yellow mass into which the greater part of the 

 hemlock oil is converted by the action of the sulphuric acid, there 

 is present a yellow oil which contains sulphuric acid combined 

 with it in a neutralized state. By the action of ether, this oil 

 may be dissolved, and by subsequent evaporation, deposited, but 

 when thus obtained it is contaminated by so much resin that 

 though the presence of sulphuric acid may be ascertained, it is 

 impossible to determine the atomic composition.* 



From the reaction of sulphuric acid, with oil of turpentine, noth- 

 ing more appears to be produced than a reciprocal decomposition ; 



* It is well known that by the reaction between chouchydrie acid and pure oil 

 of turpentine, two species of artificial camphor are generated, one solid, the other 

 liquid. Having obtained both of these compounds a few years since, Dr. Hare 

 subjected the oil of hemlock to chlorohydric acid by the same process, but could 

 not thus obtain any concrete camphor. That which he did obtain was analogous 

 to the liquid artificial camphor above mentioned. 



Vol. xxxvii, No. 2.— July-October, 1839. 32 



