68o 
[November, 
Analyses of Books. 
by the hand of man, — as if, forsooth, there could be anything 
more scientific or irrational than to relegate the acftion of known 
natural laws to a blind force.” But who limits the scope of the 
laboratory ? What, too, is the author’s definition of “ law ” as 
distinguished from “ force ” ? 
In proof of the real existence of magic the author gives a 
fearsome incident, which maybefound infull in the“ Theosophist” 
for January last. 
Any satisfactory discussion of the dotftrines thus more or less 
explicitly put forward would require an extent of space not at 
our disposal. But we think that whoever wishes to comprehend 
the recent revival of Occultism, and its possible bearings upon 
the future development of our race, will derive much benefit 
from a careful study of Mr. Oxley’s book. 
We are glad to find that the author utterly scouts the vulgar 
story of the destruction of the Alexandrian Library. Bishop 
Cyril and his monks, the murderers of Hypatia, are really the 
guilty. 
On the Amount of the Atmospheric Absorption. By S. P. 
Langley. 
This pamphlet is a communication made to the American 
National Academy of Sciences, and reprinted from the “Ame- 
rican Journal of Science.” In it the author calls in question the 
ordinary value assigned to the absorption of the solar (and 
stellar) radiations of the Earth’s atmosphere. This loss is given 
by a number of authorities, during the last and the present 
centuries, at figures differing but little from 20 per cent. So 
that, if these determinations are correCI, supposing the sky be 
unclouded and the air normally transparent, four-fifths of the 
light and heat emitted by the Sun reach the Earth’s surface at 
the level of the sea. Without impugning the accuracy of former 
observers, Mr. Langley shows that the assumption of Bouguer, 
Herschel, and Bouillet is incorreCt, and that the absorption of 
light and heat by the atmosphere is a far more complicated pro- 
cess than they supposed. Experiment shows that like propor- 
tions are not absorbed by like strata, radiant energy being not a 
single emanation, but the sum of an infinity of diverse ones, 
each with its own separate rate of absorption. 
The author then proceeds to demonstrate that the error occa- 
sioned by the ordinary assumption always tells in one direction, 
lessening the coefficient of absorption. By means of compara- 
tive observations made near the sea-level and at altitudes of 
nearly 15,000 feet he is led to infer that the mean absorption is 
double the usual estimate, or about 40 per cent. 
