PERMANGANATE OF POTASH AS A CHEMICAL ANTIDOTE. 45 



1-ecognize the fact that this rapidity ma}' be favored by the presence 

 of certain compounds. It is known that some complex organic sub- 

 stances are more readily decomposed by the permanganate salt in 

 alkaline solution than with acids, but it is believed that the reverse 

 is the case with a great majority of poisonous compounds. In general, 

 the oxidation is not only more rapid in the case where an acid is pres- 

 ent but it is also more complete, a larger amount of oxygen being 

 made available for the purpose. In some instances the amount of 

 oxygen liberated with the acid is nearly twice as great as with the 

 alkali. ^ 



Almost all of the purely medical investigators have failed to appre- 

 ciate the full value of this joint use of other substances with the per- 

 manganate solution in favoring a more rapid and complete reaction. 

 No one has laid particular stress upon the point, although Antal in his 

 tirst paper suggested that the use of vinegar or lemon juice would 

 result in the liberation of more oxygen from the permanganate. In 

 the case of the phosphorus poison, however, he considered the acid 

 unessential, and he did not make any use of the idea in his other work. 

 Schlagdenhautfen and Reeb' also noted, in 1893, that in test-tube exper- 

 iments the decomposition of coronillin, the poisonous glucoside of a 

 European leguminous plant known as CoroniUa i<eor2jioide><, was has- 

 tened not only hy the presence of sulphuric acid but by that of car- 

 bonate of soda and various salts, such as the sulphates of potassium and 

 sodium, phosphate of soda, and common salt (sodium chloride), but he 

 made no use of the suggestion, other than to show how the reaction 

 might be favored when the permanganate was injected into the blood, 

 this fluid being alkaline and containing all of the salts above-mentioned. 

 Dr. Moor has suggested an addition of sulphuric acid or white (not 

 red) vinegar to form a salt in cases where morphine, an insoluble alka- 

 loid, is in the stomach, the idea in this case being to get the alkaloid 

 into a soluble condition, in which case it will, as is the case with many 

 alkaloids, more readily unite with other compounds. 



In all of our own experiments aluminum sulphate, a common salt, 



^This is shown by the following equationiJ: 



2 KMnO,+2 KH0=2 K,Mn04^H.,0^0 

 2 KMn04-f-3 H2S04=K2SO,-f 2 MnSO^+S H^O-fS O 

 The soluble potassium manganate which is immediately formed in the first reaction 

 is gradually decomposed into the presence of water to the peroxide of manganese, 

 which is precipitated into caustic potash and into oxygen. Thus: , 



2 K.MnO^-f 2 \l.S)=2 Mn02+4 KHO+2 O 

 As seen in the second equation, the permanganate is at once decomposed into 

 manganese sulphate, a soluble salt representing the lowest oxide of manganese, and 

 at the same time a larger quantity of oxygen is liberated than m the first case, the 

 proportion for the complete reaction being three molecules for the alkali to five for 

 the acid. 

 "Jouru.der Pharmacie von EIsass-Lothnngen, vol.20, pp. 321-325. 1893. 



