Chemistry and Physics. 393 



The following formulae are given for the alkaloids of tobacco : 



Nicotine _ C 10 H 14 N 2 



Nicotimine C 10 H 14 N 2 



Nicoteine C 10 H 12 N 2 



Nicotelline _ C 10 H 8 N 2 



The following table is given as a rough estimate of the quanti- 

 ties of these alkaloids in 10 kg. of the concentrated tobacco 

 extract : 



Nicotine 1000 g. 



Nicoteine 20 g. 



Nicotimine__ _. 5 g. 



Nicotelline 1 g. 



Only one of the new alkaloids, nicoteine, has been tested in 

 regard to its physiological action. This appears to be even more 

 poisonous than nicotine itself. — Berichte, xxxiv, 696. h. l. w. 



5. The Hydrate of Sulphuryl Chloride. — B aeyee and Villiger 

 have found that when sulphuryl chloride, S0 2 C1 2 is poured into 

 ice-cold water a beautifully crystallized hydrate is formed, which, 

 curiously enough, has not been previously noticed. The sub- 

 stance has the appearance of camphor, is only very slightly solu- 

 ble in water at 0°, and in small quantities remains unchanged for 

 hours under ice-cold water. When the hydrate is slightly 

 warmed with water an oil separates which appears to be 

 unchanged sulphuryl chloride, for the hydrate is formed again 

 upon cooling. Analysis showed that the compound probably has 

 the composition represented by the formula S0 2 C1 2 .15H 2 0. — 

 Berichte, xxxiv, 736. h. l. w. 



6. The Action of Hydrogen Peroxide upon Silver Oxide. — 

 According to Thenard these two substances reduce each other with 

 the formation of oxygen, water and metallic silver. Berthelot 

 advanced the view, however, that in this reaction only the extra 

 oxygen of the hydrogen peroxide is evolved, while the oxygen 

 given up by a part of the silver is retained by another part of it 

 in the form of a higher oxide of that metal. Baeyer and Vil- 

 liger have now shown clearly that Thenard's view is entirely 

 correct, and that Berthelot was wrong in regard to this matter. 

 Since finely divided metallic silver exerts a powerful catalytic 

 action upon hydrogen peroxide, it is difficult to reduce silver 

 oxide completely by means of a solution of this substance. By 

 using about five times the theoretical quantity of hydrogen per- 

 oxide, however, and adding it slowly with thorough agitation, 

 Baeyer and Villiger have obtained a practically complete reac- 

 tion, and have found no evidence of the formation of a higher 

 oxide of silver. They have shown also that more oxygen is 

 always evolved when hydrogen peroxide acts upon silver oxide 

 than when it acts upon a simple catalytic substance like finely 

 divided platinum or silver, and that, under the proper conditions, 

 the volume of oxygen given off corresponds to Thenard's theory. 

 — Berichte, xxxiv, 749. h. l. w. 



