And seeing on the other hand that the densities attained are not 
sufficiently great to allow of the calculation of the last coefficients, 
values of “4 and /’4 and sometimes too of D4 (insofar as they had 
to be allowed for) were obtained by combining the critical constants 
published a short time ago with the set of reduced virial coefficients 
VII. 1. Solutions for the other coefficients were then obtained for 
each isotherm from a number of suitable chosen points, and were 
tested with the observed results. Finally, correspondence was made 
as satisfactory as possible either by least squares or by the method 
of KE. F. van DE SANDE BAKHUYZEN '). 
In this way the individual cvefficients for each isotherm given in 
table II were obtained. Numbers borrowed from the reduced coeffi- 
cients VIT. 1., are printed in italics. 
With these coefficients values of pv were calculated; table III 
gives percentage deviations of calculated results from observed ones. 
In this table | | and * have the same significance as before. Deviations 
placed between () are so treated because the observations to which 
they belong were not used in the adjustment of coefficients; this 
was done from consideration of the difficulty of obtaining agreement 
with a formula of whose constants only three are derived from 
observations in that neighbourhood. 
Chemistry. — “On the reaction products of potassium isocyanate 
and diaminoacetone hydrochloride. Amino- and ureopropylenc- 
ureine.” By Prof. A. P. N. FRANCHIMONT and Dr. J. V. Dupsky. 
(Communicated in the meeting of November 26, 1910). 
More than three years ago (February 23 1907) I called attention 
to the importance which the knowledge of acetoneureine would have 
in answering the question as to the action of nitric acid on hetero- 
evelie compounds consisting of two CO-, two NH- and two CH, 
groups. Of the eleven theoretically possible isomers, there are two 
which are urea derivatives, namely hydro-uracil and acetoneureine. 
The first has been investigated as to its behaviour with nitric acid 
by myself and FriepMAnn, the second has not been obtained as yet. 
1) Proc. July 1906, Comm. No. 95a. 
