Experimental machines were constructed, and after a while a practical dynamo was evolved.
Wires are attached to a dynamo and the electric current is led out.
This current may be conducted to a distant tramway car, and, by sending the current through an electric motor, mechanical motion is produced and the car propelled along.
An electric motor is practically the same as a dynamo, but instead of turning its coil round in order to produce an electric current, we pass a current into the coil and it moves round. It will be sufficient to leave the electron to tell its own story.
This is another of those roving commissions in which I have been privileged to take part on more than one occasion.
If you think of the giant size of an electric tramway car or a railway train, and try to compare one of these with an electron, such as your humble servant, it will seem quite ridiculous that I should suggest that it is we electrons who move those huge vehicles. Yet such is the actual case.
Of course we require the application of very considerable power to urge us to so heavy a task. All the energy which we can get from a few electric batteries might enable us to drive a toy car, but when it comes to turning the wheels of a real car or train, we require a correspondingly greater amount of energy.
I may as well tell you quite frankly that we electrons are only the intermediaries or go-betweens. Indeed, you must have noticed that in every case we act merely as a connecting link between matter and the æther, and between the æther and matter.
But what I want to tell you of, is the part we play in moving an electric car or railway train. It is really all very simple if you could only see it from our standpoint. Picture a host of us attached to copper atoms in a coil of wire which is being moved through that disturbed æther called a magnetic field. We are set in motion immediately. It is true that when we are moved forward into the field we march off in one direction, only to be arrested and made to move off in the opposite direction as we leave the field, but it really makes no difference in our working capabilities as long as we are kept on the move. This is what is actually taking place in the armature of a dynamo as it revolves between the poles of the electro-magnet. There is no peace for us so long as the coil is kept revolving; we are kept in a constant state of rapid to-and-fro motion.