juiyz. I9I7 Isolation of Cyanuric Acid from Soil 89 



0.029s g™- of anhydrous sample (c) required 0.009 g™- of sodium hydroxid for 



neutralization and yielded 0.00969 gm. of nitrogen; 



0.03076 gm. of the copper compound derived from sample (a) yielded 0.006765 



gm. of cupric oxid. 



Water 

 (per cent) . 



Calculated for C3H3N3O3.2H2O 21.8 



Foxmd in sample (a) 21.0 



Found in sample (c) 22. 8 



Neutraliza- 

 tion Nitrogen 

 equivalent, (per cent). 



Calculated for C3H3N3O3 129. i 32. 6 



Found in sample (a) 131. 3 32. 9 



Fotmd in sample (b) 128. 6 32. 3 



Found in sample (c) 131. i 32. 8 



Copper 

 (per cent). 



Calculated for Cu (C3H2N303)2.2NH3 17. 96 



Found in copper compound derived from sample (a) 17. 6 



The soils from which cyanuric acid has been isolated are of widely dif- 

 ferent origin and type, and it may be expected that the compound or its 

 precursor has a rather vnde distribution. The Indiana soil which yielded 

 cyanuric acid belongs to a type which is described (6) as Scottsburg silt 

 loam, light to very light ashy-gray in color, having an average depth of 

 8 to 10 inches. Fine and very fine sand mixed with the silt gives the 

 soil many of the characteristics of a fine sandy loam. As a type the soil 

 is fairly well drained. The Maine soil used in our work is Caribou loam 

 (13), devoted to potato culture. The soil is underlain at a depth rang- 

 ing from a few inches to several feet by shale. The drainage is good. 

 The Florida soil above mentioned is chiefly quartz sand and contains 

 very little organic matter. It is devoted to orange culture. The Texas 

 soil, Susquehanna fine sandy loam, is the same soil from which a-crotonic 

 acid has been isolated (11). 



Cyanuric acid, which yields two series of isomeric esters (3, p. 181) 

 and mercury salts (4), may be represented by the tautomeric formulas: 



NH N 



/ \ ^ \ 



0:C C:0 HOC C OH 



HN NH "^ N N 



\y \ / 



C COH 



O 



Lactam form. Lactim form. 



It is a polymer of cyanic acid, OC :NH. 



Cyanuric acid was probably first prepared by Scheele by heating uric 

 acid (2). In 1830 it was synthesized by Serrulas (2) by treating solid 

 cyanogen chlorid with water, and the following year Wohler prepared it 



