Such figures, such facts, stagger the imagination. The mind of man cannot really conceive them. And yet we know that they are not fanciful; calculations and indirect measurements have been made with the utmost exactitude. And, after all, the infinitely little is no more staggering than the infinitely great. For in astronomy we know that stars billions of miles distant from us in space have been seen, measured, photographed and analyzed. Tens of thousands of “light-years” separate us from them (_i. e._, space which would be travelled by light, speeding at 186,000 miles a second). And yet the structure of the atom closely resembles the planetary system! Is the whole Universe, great and small, built according to the same plan, according to the same model? It would appear so! It will be seen from the above that the modern science of chemistry overlaps other sciences in many directions--physics, biology, astronomy, etc. These sciences are to a certain extent now inter-woven and inter-blended. Where the one ends and the other begins it is hard to say. Again we see the importance of co-operation in these various fields of inquiry! THE NATURE OF MATTER These newer researches in chemistry have finally enabled us to realize the ultimate constitution of matter; we have seen that it is composed of atoms, but these atoms themselves are complex things; they in turn are composed of electrons, and in the last analysis matter may be said to be non-existent! It has been resolved into electricity. But this conception of matter has also enabled us to explain many things before inexplicable--chemical combination, radio-activity, and what not. The world-old problem as to the nature of matter has at last been solved. It now devolves upon the physicist to explain the ultimate nature of electricity! Matter, then, in a sense, can dissociate, disintegrate, dematerialize. It can also integrate, materialize, come into existence. Matter can be made to vanish and reappear. The old law of the “indestructibility of matter” is not valid, as generally understood. Matter can be resolved into energy. And this energy is radiated into space, or converted into other modes of energy, and finally into heat, which is in turn radiated into the surrounding medium. The whole universe seems to resemble a clock, which has been wound-up, and is slowly running down. Even the law of the “conservation of energy” has been called into question (See LeBon, “The Evolution of Matter,” and “The Evolution of Forces”). Is the whole Universe in some mysterious manner also being wound-up? Or does it move in vast cycles, of alternate action and inaction, as the Hindu philosophers have always contended? These are ultimate questions which only the science of the future can solve! PART II