1874.] Atomic Matter and Luminiferous Ether. 181 
That these converse qualities are necessary corollaries, 
one of another, will be evident on a brief examination; and 
whilst incidentally showing this connection, I would criticise 
those hypotheses which deny the quality of elasticity to 
tangible matter apparently possessing it, and which simul- 
taneously create a new and totally different kind of matter 
to receive it. 
Atoms are described as swinging to and fro in this won- 
derful ether, without loss of motion or of energy, and they 
consequently either impart no motion to ether, or else 
motion must be communicable to it without absorption of 
energy. But ether is a medium that transmits motion, or 
its necessity and office disappear. If atoms do move ether, 
and any energy be absorbed, the motion which is the energy 
possessed by the atoms must decrease. If no energy be 
absorbed, and yet ether be moved, then either ether move- 
ments are arrested without result or energy must be created. 
An alternative is a possibility, viz., all kinds of motion may 
be imparted to atoms, but only some kinds of motion to 
ether. 
The question then arises—Is it not easier to make atoms 
elastic and matter continuous, and so altogether avoid the 
necessity for ether? And before admitting the necessity for 
the existence of ether, it will be well to review the known 
properties of matter, and philosophically safer to imagine 
their extension in the same direCtion, even to an indefinitely 
great degree, than to imagine the existence of matter of an 
entirely different and unknown kind. 
Atomic matter forms an indefinitely small bulk in the 
universe. We see the sun, moon, and stars, and all the 
host of heaven, but when we calculate their dimensions and 
distances, and compare the bulk of these bodies with the 
bulk of the sphere of ether containing them, and by whose 
aid we know them, figures fail to convey any idea of the 
indefinitely small bulk of matter compared with the indefi- 
nitely enormous bulk of ether. 
Taking the distance of the sun from the nearest fixed 
star (a in Centaur) as the radius of a sphere of ether, and 
comparing its bulk with the bulk of our solar system, as 
being the smallest possible proportion in which atomic 
matter and ether can exist, it is as 11,000 trillions to r—a 
proportion comparable, perhaps, to a needle weighing I grain 
in a bundle of 600,000 million tons of hay, and the true 
proportion of ether to atomic matter must be indefinitely 
greater than this. Jt puts this question in a somewhat 
different light to reflect that the unique and positive qualities 
VOL. IV. (N.S.) 2A 
