108 Prof. Clausius on the Nature of the Motion 
seeds, which consist chiefly of legumine and soluble albumen, 
contain for the same quantity of phosphoric acid one and a half 
to twice as much nitrogen as the seeds of cereals, which consist 
principally of gluten. 
9. The relation of phosphoric acid to nitrogen is modified 
when one of these albuminous substances is replaced by another 
in seeds of the same kind and variety, as has been shown by 
Millon. 
10. The ash of most kinds of corn contains large quantities 
of magnesia, which is partially present as ammonio-phosphate of 
magnesia. And hence the proportion of nitrogen in a seed does 
not exactly give the quantity of albumen. 
XI. On the Nature of the Motion which we call Heat. 
By R. Criavusius*. 
1. I i perce writing my first memoir on heat, which was 
published in 1850, and in which heat is assumed to be 
a motion, I had already formed for myself a distinct conception 
of the nature of this motion, and had even employed the same 
in several investigations and calculations. In my former me- 
moirs | intentionally avoided mentioning this conception, because 
I wished to separate the conclusions which are deducible from 
certain general principles from those which presuppose a parti- 
cular kind of motion, and because I hoped to be able at some 
future time to devote a separate memoir to my notion of this 
motion and to the special conclusions which flow therefrom. 
The execution of this project, however, has been retarded longer 
than I at first expected, masmuch as the difficulties of the sub- 
ject, as well as other occupations, have hitherto prevented me 
from giving to its development that degree of completeness which 
I deemed necessary for publication. 
A memoir has lately been published by Kronig, under the 
title Grundziige einer Theorie der Gase+, in which I have re- 
cognized some of my own views. Seeing that Krénig has 
arrived at these views just as independently as I have, and has 
published them before me, all claim to priority on my part is of 
course out of the question ; nevertheless, the subject having once 
been mooted in this memoir, I feel myself induced to publish 
those parts of my own views which I have not yet found in it. 
For the present, I shall confine myself to a brief indication of a 
* From Poggendorff’s Annalen, vol. c. 
+ This was first printed separately by A. W. Hayn in Berlin, and after- 
wards appeared in Poggendorff’s Annalen, vol. xcix. p. 315. 
