That small word "Force," they make a barber's block, Ready to put on Meanings most strange and various, fit to shock Pupils of Newton.... The phrases of last century in this Linger to play tricks- Vis viva and Vis Mortua and Vis Acceleratrix:- Those long-nebbed words that to our text books still Cling by their titles, And from them creep, as entozoa will, Into our vitals. But see! Tait writes in lucid symbols clear One small equation; And Force becomes of Energy a mere Space-variation.

Science appears to us with a very different aspect after we have found out that it is not in lecture rooms only, and by means of the electric light projected on a screen, that we may witness physical phenomena, but that we may find illustrations of the highest doctrines of science in games and gymnastics, in travelling by land and by water, in storms of the air and of the sea, and wherever there is matter in motion.

Every existence above a certain rank has its singular points; the higher the rank the more of them. At these points, influences whose physical magnitude is too small to be taken account of by a finite being may produce results of the greatest importance.

Thus number may be said to rule the whole world of quantity, and the four rules of arithmetic may be regarded as the complete equipment of the mathematician.

The mathematical difficulties of the theory of rotation arise chiefly from the want of geometrical illustrations and sensible images, by which we might fix the results of analysis in our minds.

Thoroughly conscious ignorance is the prelude to every real advance in science.

The theory I propose may therefore be called a theory of the Electromagnetic Field because it has to do with the space in the neighbourhood of the electric or magnetic bodies, and it may be called a Dynamical Theory, because it assumes that in the space there is matter in motion, by which the observed electromagnetic phenomena are produced.