140 Scientific Intelligence. 
core of an electro-magnet. By means of mirrors at each end of 
the tube a ray from a lime light was made to traverse many times 
by successive reflections the column of air or gas. The principal 
magnitude as those of the magnetic rotations of the same bodies 
in the solid, liquid or gaseous states. The following conclusions 
are drawn from the investigation. 
(1) Bodies in the gaseous state, as well as solid substances and 
liquids, have the property of deviating the plane of polarization 
when submitted to magnetic influence, 
The magnetic rotations of the plane of polarization of rays 
of different wave lengths traversing the same gas (oxygen ex- 
cepted) are generally inversely as the squares of the length of 
i d 
xygen presents an anomaly which is apparently connected 
gas.— Annales 
T 
q Fe ° ° 
The influence of Gases and Steam upon the Optical proper 
5 . m 
are not condensed in a quantity apparent to the eye, no change 
of phase takes place in reflection.— Ann. der Physik und Chemie, 
Nov. 11, 1880. =f Shia 
10. A Physical Treatise on Electricity and Magnetism; by J. 
E. H. Gorpon, B.A., Cambridge. 8vo. (D. Appleton & Co.,N. Y.) 
gram would have answered i ny cases better than the 
finely finished perspective views, and there would have been more 
for solid informati A full page, for instance, is given to 
on 
catalogues, 
