THE 
JOURNAL OF SCIENCE 
OCTOBER, 1880. 
I. THE VEHICLE OF FORCE. 
By Charles Morris. 
ODERN thought has made so many valuable con- 
quests in the outlying distridts of the kingdom of 
Science that it is daily drawing nearer, to the citadel 
of the kingdom, that abstruse question of the ultimates of 
Nature on which so much deep reasoning has been expended, 
yet which still remains unsolved. The whole process of 
thought in this direction has been a process of simplification. 
A century ago a very complex conception of these ultimates 
was entertained. To ordinary matter was added an indefi- 
nite number of imponderables, while the forces of attraction 
and repulsion were neatly parcelled out among these various 
forms of substance, until the whole affair became unplea- 
santly intricate. As for motion, there had been some inquiry 
into its laws, but very little consideration had been given to 
its office as a primary constituent of Nature. 
We have changed all that. The imponderables have 
ceased to be substances, and have become special modes of 
motion ; and Nature is being reduced in theory to two ulti- 
mates, matter and motion. True, matter has not quite 
reached this degree of simplification. There still underlies 
it a vague conception of an unparticled Ether, the supposed 
vehicle of radiant force. This ethereal constituent of Nature 
has been found necessary by two classes of reasoners, — the 
students of the science of Optics, and the promulgators of 
force theories. It has seemed impossible to explain Attrac- 
tion and Repulsion as attributes of a single form of matter, 
and theorists have found themselves obliged to deal with 
two diverse substances, through whose aid they neatly make 
VOL II. (THIRD SERIES). % T 
