( 704 ) 



is also shown l>v the faci that, the colour having become blue 

 or green on cooling, turns again violet on warming, so long as 

 the solid phase S lias not jet been attained. The phase is, therefore, 

 realisable at a change of temperature in two directions. 



§ 7. As I had but very little of the substance at ray disposal, 

 the thermometric determinations could only be studied in capillary 

 tubes with the aid of a magnifying glass. 



At 82. °1 the phase S melts to a doubly -refracting phase B which 

 becomes clear at 86. c 4 and passes into L. On cooling this isotropons 

 fusion, it first passes properly into 1> at 86\4, but at 84° into the 

 more strongly doubly-refracting phase A, which may be undercooled 

 many tens of degrees, and with retention of its violet colour, before 

 passing into the solid phase S. 



Want of material prevented my determining the true solidifying 

 point of S by inoculation; I estimate it at about 80°. 



Thus the positive proof has been given that the remarkable colour 

 phenomena accompanying the melting the cholesterol esters cannot be 

 attributed to the presence of an ethylene double bound; also that 

 an eventual presence of fumaroid and maleinoid isomers cannot be 

 considered as the cause of the occurrence of the three liquids. 



Zaandam, 15 Febr. 1907. 



Chemistry. — "On the action of buses, ammonia and a mini's on 

 s. trinitrophenyl-methylnitramine." By Prof. P. van Rombürgh 

 and Dr. A. D. Maurenbrecher. 



(Communicated in the meeting of February 23, 1907). 



s. -Trinitrophenyl-methylnitramine, as has been known for a long 

 time, is decomposed at the ordinary temperature by ammonia in 

 alcoholic solution, or on warming, by an aqueous solution of potas- 

 sium hydroxide, or carbonate, in the tirst case with formation of 

 picramide, in the second (with evolution of mononiethylamine) of 

 picric acid. One of us who formerly studied the reaction with bases 

 concluded, from the occurrence of the amine and the formation of 

 nitric acid which was also observed, that the methj lnitramine which 

 might be expected according to the equation : 



