1835.] Analyses of Books. 383 



rhomboidal prisms, with a fine lustre, and white colour. 

 It is strongly alkaline. 



When exposed to the temperature of 266° it fuses, and 

 becomes solid at 230°. Narcotine fuses at 338°, and solidi- 

 fies at 266°. Codeine fuses at 302, and meconine at 194°. 



The strong acids convert thebaine into resin, and when 

 diluted form crystallizable salts. The following results 

 were obtained by Couerbe : — 



Carbon. Oxygen. 

 Narceine . . 56-818 - 31-900 

 Thebaine . . 71-976 - 15-279 

 Codeine . . 72-846 - 14-775 



The paramorphine of Pelletier was obtained by Thibou- 

 mery by treating the infusion of opium with slacked lime. 

 He obtained by this means a clear liquid, and a precipitate 

 containing much lime, which was treated with alcohol, and 

 the solution gave, instead of morphine, this new substance, 

 which appears the same as the thebaine of Couerbe. 



The proportion of morphine in opium, Couerbe states may 

 be determined in the course of two hours, by boiling the 

 infusion of opium with an excess of lime, and passing the 

 solution through a filter. If an acid be added, taking care 

 not to add it in excess, the morphine precipitates. 



Article IX. 



ANALYSES OF BOOKS. 



I. — Poggendorff's Annalen der Physik und Chemie, 

 Band, xxxiv. 1835. 



Description of a Barometer, by C. Brunner of Bern. 



The author observes that the atmospherical pressure may be 

 measured in two different ways, either by observing the height of a 

 hquid column contained in a tube, the upper part of which is deprived 

 of air, and the lower extremity is exposed to the excess of the atmos-i 

 phere, as in the common barometer, or by the volume which a gas 

 occupies in a closed vessel, when the latter is completely elastic, or 

 the act of enclosing the gas in the vessel is effected without percep- 

 tible resistance. 



The apparatus of Varignon, described in 1705 ; the sympiesometer 

 of Adie the baroskope of Prechtl, and the differential barometer 

 of August, are examples of the latter. He then proceeds to describe 



