92 



EEPOET OF CHEMICAL LABORATORY 



Further 

 examination 



The time at disposal has not permitted of any thorough investigation, but the following 

 observations have been made. The acid liquid [(a) in Table A] left after the removal 

 of the lead salt was treated with ammonia until no further precipitation took place. 

 After filtration, the alkaline liquid was boiled until free from ammonia, and the lead 

 removed by sulphuretted hydrogen. The liquid was freed from sulphuretted hydrogen 

 by a current of air, filtered, and concentrated. This concentrated liquid gave amorphous 

 precipitates with tannic and picric acids, mercuric chloride, iodine, Meyer's reagent, 

 and phosphomolybdic acid, and with basic lead acetate, the latter being soluble in excess. 

 The tannic acid precipitate was soluble on boiling, reappearing when the solution was 

 cooled, a reaction characteristic of the proteids. The examination of this liquid is 

 proceeding. 



The lead compound [(d) Table A] produced by the addition of ammonia and basic 

 lead acetate to the filtrate from neutral lead acetate was washed, suspended in water, 

 and decomposed by sulphuretted hydrogen. After filtration, and removal of excess si;l- 

 phuretted hydrogen by a current of air, the solution was concentrated on the water-bath. 

 Tliis concentrated solution gave a deep blue coloration with the sulphuric acid reagent. 

 Attempts to obtain from it anything of a crystalline nature were unsuccessful ; on evapora- 

 tion to dryness a brown amorphous residue was obtained. 



Tlie charcoal residue [(a) Table B], previously washed with water, and dried over 

 sulphuric acid, was extracted with absolute alcohol, and the alcoholic solution evaporated 

 to dryness. A small quantity of a brown, gummy, and somswhat resinous residue, acrid to 

 the taste, and only partially soluble in cold water, was left. This was dissolved in hot 

 water, cooled and extracted with ether. The aqueous liquid, which was distinctly acid 

 to litmus, did not reduce Fehling's solution, even after hydrolysis, but gave voluminous 

 precipitates with tannic acid, picric acid, mercuric chloride, iodine, potassium-bismuthic- 

 iodide, and phosphomolybdic acid, and a deep blue colour with the sulphuric acid 

 reagent. The precipitates were amorphous, and the picric acid precipitate was soluble 

 on boiling, re-forming on cooling. The ethereal liquid left a small quantity of a resin-like 

 substance on evaporation. 



On making the aqueous liquid alkaline with annuonia and extracting with ether, a 

 w'hite amorphous residue, sparingly soluble in ether, insoluble in cold water, but readily 

 soluble in alcohol and chloroform, was obtained. This substance has not yet been 

 further examined. 



The filtrate from the animal charcoal [(b) Table B] was evaporated on the water-hath 

 to a syrupy consistency, and allowed to evaporate slowly over sulpluiric acid. A large 

 quantity of crystalline salts was deposited, extremely soluble in water, but insolul)lc in 

 alcohol. On evaporating the syrupy liquid to dryness, a yellow, crumbly, sugar-like mass 

 remained, which chan-ed on heating in a dry tube, with the formation of an amorphous 

 sublimate, soluble in cold water, and strongly acid to litmus. The charred residue was 

 alkaline, and consisted chiefly of magnesium oxide. 



Toxicity 



Animal 

 experiments 



Toxicity of the Latex 



Experiments have been carried out to determine the toxicity of the latex by 

 subcutaneous injection and by feeding. Rabbits were the only animals used in these 

 experiments. With regard to subcutaneous inoculation, one rabbit w-as inoculated with a 

 quantity of the decomposed ammonium hydrate pi-ecipitate [ (d) Table A] corresponding 

 to 0-2 c.c. latex. Another rabbit was inoculated with the filtrate from the basic lead 

 acetate precipitate [ (c) Table A] corresponding also to 02 c.c. latex. A third rabbit 



