258 PROCEEDINGS OF THE AMERICAN ACADEMY 



alcohol, and insoluble in ether. Concentrated sulphuric and hydro- 

 chloric acids dissolve it readily, and deposit the greater portion upon 

 dilution. 



The slender oblique prisms in which methyluric acid ordinarily 

 crytallizes contain one molecule of water when dried in vacuo over 

 sulphuric acid. 



0.6067 gr. lost at 160° 0.0511 gr. H.,0 — 8.49%. 



The formula C 5 H s (CH,) g N 4 3 . H 2 requires 8.41%. 



The crystals of the second form were obtained for analysis by 

 evaporating a saturated solution of the acid upon the water-bath, and 

 filtering hot. Although our determinations agree closely with the 

 amount required for a half-molecule of water, it is not impossible that 

 the loss in weight is due to hygroscopic moisture, as was the case with 

 the monomethyl acid. 



I. 0.4547 gr. substance dried in vacuo lost at 160° 0.019G gr. 

 HX> = 4.31%. 

 II. 0.2651 gr. lost 0.0114 gr. H 2 = 4.30%. 



The formula C s H 2 (CH 3 ) 2 N 4 3 . £H 2 requires 4.39%. 

 The composition of the substance dried at 160° was determined by 

 the following anahyses : — 



I. 0.2747 gr. gave 0.1097 gr. H 2 and 0.4291 gr. C0 2 . 

 II. 0.2022 gr. gave 0.0789 gr. 11,0 and 0.3167 gr. C0 2 . 



III. 0.1393 gr. gave 0.0557 gr. H 2 and 0.2185 gr. C0 2 . 



IV. 0.3521 gr. gave 86 cc. nitrogen at 16° and 756.5 mm. pressure. 



28.21 



The solubility in boiling water was determined by filtering a boil- 

 ing saturated solution through a hot-water filter into weighed flasks. 

 After cooling, the flasks were weighed, the contents transferred to 

 platinum dishes, evaporated to dryness, and the residue dried at 165°. 



I. 54.2110 gr. solution left 0.2043 gr. residue. 

 II. 57.8596 gr. solution left 0.2940 gr. residue. 



The boiling saturated solution contains the following percentages : — 



1. 2. 



0.5152 0.5081 



