282 CHEMISTRY OF THE PTOMAINS. 



is Cj^HgjNj. The free base has not been obtained. The hydrochlorid 

 forms a light-yellow syrup which shows no tendency to crystallize. 

 It is soluble in water and in absolute alcohol, and is somewhat hy- 

 groscopic. 



When heated with fixed alkali it gives off a strong amin odor, 

 such as is perceived on evaporating the original culture fluid, if it 

 happens to be alkaline in reaction. 



The platinochlorid is obtained by precipitation as a light, flesh- 

 colored, granular precipitate. It is readily soluble in water, from 

 which it can be reprecipitated by addition of absolute alcohol. 

 From aqueous solution, when allowed to evaporate slowly, it crys- 

 tallizes in long, thick needles. 



The mercurochlorid is thrown down from solutions of the hydro- 

 chlorid in absolute alcohol, by alcoholic mercuric chlorid, as a 

 heavy, white, granular precipitate. This readily dissolves on the 

 addition of a small quantity of water, and can be perfectly reprecip- 

 itated by addition of absolute alcohol. On treatment with hydrogen 

 sulphid it is readily decomposed, yielding the pure hydrochlorid. 



The aurochlorid is very soluble in water and alcohol. From the 

 alcoholic solution it may be partially precipitated by ether as a light- 

 yellow, oily precipitate, which is adherent to the sides and bottom of 

 the tube. 



The base is toxic only in relatively large doses, as seen from the 

 following experiment. About 100 milligrams, dissolved in a little 

 water, were injected subcutaneously into a young rat. The animal 

 was at first quiet, apparently unwilling to move. After some inef- 

 fectual attempts at jumping it settled down to a recumbent position, 

 and when placed on its side was unable to rise. Respiration was at 

 first retarded, later increased, but toward the end was again very 

 slow. Convulsive tremors shook the body at frequent intervals. 

 The animal kicked vigorously. Reflexes were present almost to the 

 end. As death approached the red eyes whitened and took on a 

 glazed, opaque appearance. Death resulted in one and a half hours. 

 The animal was on its side, the feet extended. Post-mortem exam- 

 ination showed the heart arrested in diastole, lungs rather pale, 

 stomach contracted, serum in thoracic cavity, subcuta pale and 

 €edematous. Repeated doses of smaller quantities seem to confer a 

 partial immunity to the action of the germ. 



/NH.CH, 

 Methyl guanidin, C,H,Ns , nh = C<^ . This base has long 



been known as a product of the oxidation of creatin and crea- 

 tinin, but has never been met with in animal tissues. Brieger 

 in 1886 (III., 33) obtained it from horseflesh which was al- 

 lowed to decompose in a closed vessel at a low temperature (—9° 

 to -|- 5°) for four months. Bocklisch {Ber., 20, 1441) isolated it 



