316 Intelligence and Miscellaneous Articles, 



1 . In passing a current of oxide of carbon into a solution of pro- 

 tochloride of copper in hydrochloric acid, the gas was absorbed in 

 considerable quantity, and with a rapidity comparable to that with 

 which carbonic acid is absorbed by potash ; but the temperature was 

 comparatively but slightly raised. 



2. The ammoniacal protochloride of copper, out of the contact of 

 the air, acts in the same manner, and the quantity of gas absorbed 

 is the same for the same quantity of copper dissolved. This solution 

 becomes blue afterwards by exposure to the air, and may again serve 

 to absorb oxygen. 



3. The acid protochloride of copper, saturated with oxide of car- 

 bon, may be diluted even with a large quantity of water without 

 precipitating protochloride of copper, as before absorption, and with- 

 out any disengagement of gas. The addition of alcohol does not 

 render it turbid. vEther appears to destroy, at least partially, the 

 compound which M. Leblanc has not hitherto been able to isolate. 

 Ebullition or a perfect vacuum expels the gas. 



4. The fact of the absorption of oxide of carbon by the proto- 

 chloride of copper appears to be of the same order as the absorption 

 of nitric oxide by the salts of protoxide of iron, inasmuch as the 

 absorption appears to occur in definite proportions. The numbers 

 approximate equal equivalents of copper and oxide of carbon. 



5. The protosalts of iron or tin do not act upon oxide of carbon. 



6. The various salts of protoxide [suboxide ?] of copper dissolved 

 in ammonia absorb oxide of carbon like the protochloride of copper. 



7. Cyanogen is also absorbed by protochloride of copper; there 

 is then formed a deposit of a chrome-yellow colour, which is rapidly 

 modified in the air, — Journ. de Chim. Med., Juillet 1850. 



ON A CAUSE OF VARIATION IN THE ANGLES OF CRYSTALS. 

 BY M. J. NICKLES. 



The author states that the cause is the intervention of foreign 

 substances. In September 1849 he pointed out this cause in the 

 variations of the angles of the prisms of sugar of gelatine ; and he 

 now adduces a new fact which readily allows of verifying the influ- 

 ence that a small quantity of foreign substances may exert on the 

 crystalline form of bodies which are deposited in its presence. When 

 a solution of chloride of cobalt containing an excess of sal-ammoniac 

 is allowed to evaporate spontaneously, crystals of the last-mentioned 

 salt are obtained which are more or less coloured, the angles of which 

 are always near, but never 90° : the difference often exceeds 7°, and 

 yet these crystals contain only 0*5 to 1 per cent, of chloride of co- 

 balt. The same fact has been observed with respect to crystals of 

 hydrochlorate of ammonia deposited in the presence of bichloride of 

 platina, chloride of nickel, and also with chloride of potassium depo- 

 sited under similar circumstances. — L'lnstitut, No. 852. 



