288 PROCEEDINGS OF THE AMERICAN ACADEMY 



The air-dried substance lost 0.0015 gr. at 56°, and showed a 

 tendency to sublime at 105°. 



II. 0.2126 gr. of the compound dried at 105° gave on combustion 

 0.2105 gr. of carbonic dioxide and 0.0304 gr. of water. 

 III. 0.2260 gr. of the compound dried at 105° gave 31.2 c.c. of nitro- 

 gen at a temperature of 17° and a pressure of 775.8 mm. 



Calculated for Found. 



C 6 (OH) 3 (N0 2 ) 3 . II. in. 



Carbon 27.58 27.01* 



Hydrogen 1.15 1.59 



Nitrogen 16.09 16.37 



It is evident from these analyses that the substance is trinitro- 

 phloroglucine, and therefore it becomes important to explain the very 

 marked difference between the melting points observed by Benedikt 

 and by us. We are inclined to ascribe this to the water of crystal- 

 lization, as the melting point 167° was obtained with the substance 

 dried at 105° used for analysis, whereas with samples which had 

 been only air dried (or dried at 50°) we obtained melting points 

 as low as 160-161°, that is, only 2° or 3° above the 158° obtained 

 by Benedikt. 



In order to determine whether the formation of the trinitrophlo- 

 roglucine and its diethylether was due to a direct reaction, or to the 

 secondary reaction on the trinitrophloroglucine triethylether of some 

 sodic hydrate formed by the moisture of the air acting on the sodic 

 ethylate, the following experiment was tried. Absolute alcohol made 

 in the usual way with quick-lime was treated with a small quan- 

 tity of sodium, and then the unaltered alcohol distilled off from the 

 sodic alcoholate in a perfectly dry apparatus, which communicated 

 with the outer air only through a drying tube; to the distillate in 

 the flask which served as a receiver, a quantity of bright sodium 

 was added as quickly as possible, after which it was closed at once 

 with a cork carrying a drying tube. When the reaction was at an 

 end, and the solution of sodic ethylate had cooled, 5 gr. of dry 

 tribromtrinitrobenzol were added, and the mixture allowed to stand 

 over night closed with the cork carrying the drying tube. The 

 solution, which had turned red, was acidified with dilute sulphuric 



* The percentages of carbon and hydrogen are as near to those required by 

 the formula as could be expected when the difficulty of making a combustion of 

 this explosive substance is considered. 



