2 
excep A 2. E ees te Pe ae aaa et ee Se eae 
a EŞ 
tainly t 
ew 
ADDRESS OF PROFESSOR LOVERING. 649 
kept open, and the dust and cobwebs which Newton had swept 
from the skies should not reappear. Prophetic eyes contemplated 
the possibility of an untimely end to the revolution of planets, if 
their ever expanding atmospheres should rush in to fill the room 
vacated by the maelstroms of Descartes. When it was stated 
that the absence of infinite divisibility in matter, or the coldness 
Of space, would place a limit upon expansion, and, at the worst, 
that the medium would be too attenuated to produce a sensible 
check in the headway of planets, and when, in more recent times, 
even Encke’s comet showed but the slightest symptoms of 
mechanical decay, it was believed that the motion was, in a prac- 
tical, if not in a mathematical sense, perpetual, Thus it was that 
the splendors of analysis dimmed the eyes of science to the in- 
trinsic difficulties of Newton’s theory, and familiarity with the 
language of attraction concealed the mystery that was lurking 
beneath it. A long experience in the treatment of gravitation 
had supplied mathematicians with a fund of methods and formulas 
Suited to similar cases. As soon as electricity, magnetism and 
lectro-magnetism took form, they also were fitted out with a gar- 
ment of attractive and repulsive forces acting at a distance: and 
the theories of Cavendish, Poisson, Aepinus and Ampere, endorsed 
as they were by such names as Laplace, Plana, Liouville and 
Green, met with general acceptance. 
„~ae seeds, which were destined to take root in a later genera- 
tion, and disturb if not dislodge the prevalent interpretation of 
the force of gravitation, were sown by a contemporary of Newton. 
found no congenial soil in which they could germinate and 
fructify until the early part of the present century. At the 
Present moment, we find the luminiferous ether in quiet and undi- 
_ | CS Possession of the field from which the grosser material of 
“neient systems had been banished. The plenum reigns every- 
Where; the vacuum is nowhere. Even the corpuscular theory of 
_ it, as it came from the hands of its founder, required the rein- 
ent of an ether. Electricity and magnetism, on a smaller 
< > applied similar machinery. If there was a fundamental 
“on to the conception of forces acting at a distance, cer- 
bridge was already built by which the difficulty could be 
nted. The turning-point between the old physics and the 
Phy sics was reached in 1837, when Faraday published his 
ients on the specific inductive capacity of substances. 
