PRESIDENTIAL ADDRESSES. 23 
livered April 30, 1897, presented mathematical results indicating that the ‘‘ par- 
ticles carrying the electric charges’’ in those rays must be very much smaller 
than the hydrogen atom. 
But before we speak further of the protatom and the role it is to play in our 
theory of the cosmos, let us examine the prevalent theory of the ether as set forth 
by modern physicists. By them the ether is defined as a continuous medium 
pervading all space, intermolecular and interatomic, as well as interstellar; per- 
fectly elastic and exceedingly attenuated ; without gravity; imponderable. There 
are here several qualities assigned to the ether which are contradictory and, for 
that reason, illogical. How can a substance be elastic and at the same time ab- 
solutely continuous? To be elastic it must yield to stress or pressure in the re- 
gion where the strain is applied, and then, on the removal of the stress, it must 
return completely to its original position, if perfectly elastic. Now, if a space be 
already full of the ether as such, how is more of it to be conceived to be crowded 
into that space? ‘ By making the ether more dense in that particular region,” it 
may be said. But ‘‘density’’ isarelative term, and implies that a greater or less 
quantity of matter occupies a definite volume. The quality ‘‘density’’ cannot 
logically be predicated of a substance which is already supposed to /il/ all space. 
If a measured space is absolutely filled with a substance no more can be intro- 
duced, and none can be abstracted without leaving the space incompletely filled. 
Here, then, we find a plain contradiction of statement, when it is asserted of the 
ether that it is perfectly elastic and also that it occupies all space. 
The ether is also said to be ‘‘imponderable.’’ If that be the case, how can it 
have mass? How can it resist action and thereby produce reaction? That is: 
how can it propagate energy, or convey energy, or impart energy? That it does all 
this we know from the phenomena of light, electricity, and radiant heat. In a 
certain sense a mass may be so positioned that it will ‘‘ weigh nothing,’’ as would 
be the case of an object located between the earth and the moon at the place where 
the ‘‘attractive forces’’ of the planet and satellite exactly neutralize each other; 
but even in that unique position that object would not be imponderable in the 
sense in which that term is meant to be applied to the ether. Just as much 
force would be requisite to impart to a unit mass of that object a velocity of one 
centimeter in one second out there in space as would be necessary were it at the 
earth or were it located anywhere else in the universe. Balancing the forces at 
play on a mass does not render it imponderable. Were the mass imponderable, 
it could be put in motion at any velocity whatever without the application of 
force. This is impossible with any mass whatever; therefore the term ‘‘impon- 
derable,’’ in its true physical sense, cannot be applied to matter of any kind. 
Now, we know force is necessary to produce motion in the ether. The carbon 
filament in an incandescent lamp must be at least red-hot in order to establish 
those waves in the ether we call light. .A dynamo must be run by a steam-engine 
or by some other power to induce those waves in the ether about conductors, 
which waves we call electricity, and the energy of which waves brought under 
control runs our street-cars and turns the night of our cities into day. There is 
every evidence that a dyne force would be necessary to impart to a gram mass of 
the ether a velocity of one centimeter in one second, as is the case with all other 
forms of matter. The ether is therefore ponderable, and a gram mass of it would 
be such quantity as a force of one dyne could bring to a velocity of one centime- 
ter per second, if applied for that interval. 
Let us have a better notion of the ether than this attempt at a conception of 
an imponderable yet forceful, exceedingly attenuated yet infinitely continuous, 
perfectly elastic yet incompressible, all-pervading, incomprehensible form of 
