PROCEEDINGS. 
399 
Mr. F. W. Clarke read a paper on A new law in thermo¬ 
chemistry. He finds that, after correcting the data given by 
Berthelot, Thomsen, and others for gain or loss of heat due to 
change of state and the amount absorbed in decompositions, the 
absolute heat of formation of any chemical compound is a func¬ 
tion of the number of atomic linkings or unions in the molecule; 
in certain series it is directly proportional to the number of 
these unions, and in any organic compound is an integral mul¬ 
tiple of a constant, which is about 13,777 calories. The thermal 
value of a union between two atoms is independent of their 
masses. The absolute heats of formation of corresponding 
chlorides, bromides, and iodides are equal. This at once sug¬ 
gests a correlation between thermo-chemical data and Faraday’s 
law. [Published in Washington Academy of Sciences Proceed¬ 
ings, vol. v, p. 1.] 
The paper was discussed by Messrs. Baker, Thompson, Wead, 
and King. 
Mr. J. D. Thompson then explained the principles of the 
Reclassification of the science section in the Library of Congress. 
All the books are to be grouped in 26 sections, lettered A to Z; 
Q is assigned to science; a second letter gives the next subdivision, 
and then follow numbers, as Q A 503; in a second line the famil¬ 
iar Cutter’s author-abbreviations are given. The division is to 
be rather minute to serve the needs of students, who will be 
liberally admitted to the shelves. 
The paper was discussed by Messrs. Clarke, Baker, Green, 
and Rathbun. 
556th Meeting. October 25, 1902. 
President Rathbun in the chair. 
Thirty persons present. 
Mr. S. W. Stratton spoke on The present status of the 
Metric System in the United States and Great Britain, detailing 
the various attempts to obtain permissive legislation, and some of 
the various bodies that had forwarded memorials to Congress. 
[Not published.] 
