Intelligejice and Miscellaneous Articles. 363 



posed narcotina, the solution is to be heated to ebullition, and after- 

 wards saturated with carbonate of soda, and the oxide of manganese 

 precipitated is to be separated by filtration ; the filtered liquid neu- 

 tralized with hydrochloric acid is to be precipitated with chloride of 

 platina, which forms a difficultly soluble compound with the new 

 base, so that it may be washed with cold water ; these precipitations 

 must not, however, be made in solutions which are very dilute ; the 

 precipitation may also be eflFected by bichloride of mercury. 



The author at first employed another method, but it is probable 

 that a portion of the new base was decomposed by the excess of 

 soda ; it is, however, mentioned as probably serving to explain the 

 formation of a body hereafter to be noticed. 



The mother- waters above mentioned are to be much concentrated, 

 so as to separate a large proportion of the salt of manganese ; it is 

 then, after filtration, to be treated with excess of carbonate of soda 

 and evaporated to dryness. The dry mass treated with alcohol dis- 

 solves some substances which give it a deep brown colour, and the 

 solution has a very bitter taste. The alcohol is afterwards evapo- 

 rated, the syrupy residue is to be diluted with water and neutralized 

 with a little hydrochloric acid, and then mixed hot with a solution of 

 chloride of platina ; on cooling the double salt is deposited in trans- 

 parent mammillated masses of a reddish-yellow colour. 



The double salt prepared in this manner could not contain any 

 narcotina ; excess of peroxide of manganese and sulphuric acid had 

 been employed in the preparation ; the ebullition of the mixture had 

 been long continued, and the mixture had besides been treated with 

 soda, so that ammonia did not precipitate any narcotina. 



The narcotina [platina ?] was separated from this salt by powder- 

 ing it and putting it into boiling water, into which sulphuretted hy- 

 drogen was passed. The yellow liquid which filters on separating 

 the sulphuret of platina, retains hydrochlorate of cotarnina, and is af- 

 terwards treated with hydrate of barytes. It is then to be evaporated 

 to dryness and treated with alcohol, which leaves carbonate of barytes 

 and chloride of barium. 



Cotarnina was obtained in the form of a radiated yellow mass. 

 Water and alcohol dissolve it readily, and assume an intense yellow 

 colour. It has a very bitter taste and a slightly alkaline reaction. 

 When heated it fuses and carbonizes, emitting a disagreeable smell. 

 The charcoal is difficult of incineration, but it burns without residue. 



When dried after saturation with hydrochloric acid, it forms a 

 yellow amorphous mass, in which crystalline nuclei are sometime* 

 perceptible. The alkalies do not precipitate it from its solution in 

 hydrochloric acid, but it is thrown down by the chlorides of mercury 

 and platina, and by tannic acid. 



The double salt of mercury is a bulky precipitate of a pale yellow 

 colour, which soon becomes crystalline. In hot weak solutions no 

 precipitation takes place, but on cooling, the salt is deposited in small 

 pale yellow prisms. When attempts are made to recrystallize it, it 

 appears to undergo some modification as to its composition. 



The double salt of platina, formed in cold solutions, very much 



