Review of Recent Oeological Literature. 301 
quotes the authority of Newton himself, who denied with emphasis 
the possibility of any such energy as residing in tiie partiolos of mat- 
ter. The theory of the author is considered under two heads : (1) The 
efficient cause of gravitation, and, (2) The mode of its operation. 
The waves of heat that radiate from the sun, and all suns, carried 
through space by the undulations of the universal ether, undergo 
such modifications that they appear under the guises of several spec- 
ialized forms of force ; one of them being mechanical force, or that in- 
finitesimal impact which each particle of each moving wave bestows 
on the particle of matter with which it comes in contact. This spec, 
ializationof the energy that is carried in the waves of the ether oper- 
ates in all directions and in right lines, without interference with it- 
self. They are the impulses that matter transmits, through the ether, 
to other matter, the beginning of which is coeval with the beginning 
of things. Thus while the seat of gravitation is in the ether, the ether 
is only the proximate cause, the transmitting cause. The cause itself 
is in other matter, but that again acts only as it is acted upon by other 
ether. Hence the operation is a round, from cause to effect, which 
again become a cause and an effect, and so on ceaselessly. 
As to the mode of action of gravitation — As matter intercepts some 
portion of the impulse of a wave of ether that impinges upon it, the 
leeward side of such a mass is in a shadow from that amount of im- 
pulse, and if another mass happen to be in the line of that shadow 
it is sheltered on that side. Indeed they mutually shelter each other 
from those impulses that would pass in right lines through lioth. In 
other words the impulses that impinge on their unsheltered sides 
drive them together, and the force with which they approach each 
other is gravitation. Every particle of matter is thus impelled toward 
every other particle by propulsive forces varying directly as the masses 
and inversely as the square of the distance between their centres. 
The machinery of the planetary systems, as outlined in astronomical 
mathematics, would move on as smoothly under the sway of a univer- 
sal propulsive force, as of a universal attractive force, and all the laws 
of astronomical physics, so far as they would be needed to maintain 
the universal motion, would be as rigidly observed. "Let a large 
round table be placed in the middle of a room ; place a wooden globe 
in the centre with any number of equidistant radii composed of rigid 
rods projecting from its equator. Station around it an equal number 
of boys, of exactly equal strength, one to each rod. No matter wheth- 
they all push or pull, the pushes or pulls will neutralize each other, 
and the gl6be will remain unmoved. But this is not the case with the 
earth. She is slowly, compared with her onward motion, falling 
toward the sun. * * * * If w« suppose the boys to be pushing on 
this wooden globe, we must, to adapt the comparison to the case in 
hand, withdraw one of the boys, say from the south side of the table, 
then if all the remaining boys push with ec)ual force, the globe will 
slowly move toward the side of the table where the resistance is the 
