272 Scientific Intelligence. 
surface of cooling. 
ese markings may have been observed by others; and 
as soon as the subject can be examined on other irons, a better 
conclusion can be formed. 
SCIENTIFIC INTELLIGENCE. 
I. PHYSICS AND CHEMISTRY. 
_1. On the wave lengths of the metallic rays.—THAL&n has ee | 
lished an extended memoir on the wave lengths of the spect | 
new measurements, but is based upon those made by Angstrom, 
which had already been employed for the purpose of interpola 
tion by the writer of these notices. The method of proc ¢ 
ing was however new. ach luminous ray, the wave length % 
which was to be measured, was in the first place entered either 
rays were then transferred to the norm $ 
furnished _Angstrém, and finally were entered upon the et 
published with Thalén’s memoir. each being placed ac 
