*24;4! Intelligence and Miscellaneous Articles. 



oil is a colourless liquid of great limpidity and fluidity, and a pleasant 

 odour ; its density at about 52° F. is 0*849 ; its mean index of re- 

 fraction is 1*4719 at 56° ; that is to say, it is the same as that of oil 

 of turpentine and the greater number of its isomeric compounds. Its 

 rotary power is 90°*30, it is consequently one of the substances 

 which turns most strongly to the left. 



Its boiling-point is remarkably fixed (which, the author remark?, 

 all essential oils do not possess), and is about 345° F. under a pres- 

 sure of 755 millimetres. M. Deville found the oil of elemi, like Mr. 

 Stenhouse, to be similarly composed with the oil of turpentine, 

 lemons, &c, : 



I. II. 



Hydrogen.... 11-9 11-9 11-761 pzouis 



Carbon 88-0 88-1 11-76/ 



Loss "1 



1000 100-0 100-00 



The density of the A'apour was found to be the same as that of oil 

 of turpentine; by experiment it was 4-84; calculation gives 4-76. 

 Contrary to the observation of Mr. Stenhouse, the author was able 

 to obtain two camphors of elemi, one of which is solid and crystalline 

 and the other liquid. Both have the same composition, and are iso- 

 meric with the camphors of lemon. The following are the author's 

 analyses : — 



Experiment. Calculation. (C^''H^ HCl) 



^ ^ ^ 



Carbon 57-3 57-3 57-5 57*4 



Hydrogen 8-7 8-7 8-7 8-6 



Chlorine 34-0 34-0 338 34-0 



1000 1000 100-0 100-0 



The quantity of hydrochloric acid absorbed by oil of elemi is con- 

 siderable, amounting to 47 '7 per cent, of the weight of the oil ; and 

 in order to obtain the crystallized camphor, the current of gas must 

 be continued long after the period at which the saturation appears 

 to be complete. The matter is then liquid, but the soHd camphor 

 is readily deposited after the excess of acid has escaped by exposure 

 to the air. The rotation of this camphor is nil, like that of its isomer, 

 camphor of lemons. — Ann. de Ch. ei de Phys., Septembre 1849. 



ACTION OF NITRIC ACID ON RHUBARB. BY M. GAROT. 



It results from the author's experiments, that when one i)art of 

 rhubarb is treated with four parts of nitric acid, there remains 

 a peculiar substance unacted upon by the acid, amounting to 8 or 

 10 per cent, in indigenous rhubarb, and 15 to 20 per cent, in foreign. 



This matterj to which it is proposed to give the name of erythrosin, 

 is yellow when obtained from indigenous rhubarb, and orange- 



