Not less startling is it to be told that a question may yet be raised which will challenge "the conception of a luminiferous aether, which for half a century has dominated physical science. It is possible," so we are informed, "that the field of electro-magnetic energy surrounding an electric charge in motion moves with it, and that the vibrations of light travel through this moving { 74} field, instead of through an ocean of stagnant aether."[4]
One further quotation of singular interest may be added. It is taken from an address to students by the President of the Institution of Mining and Metallurgy.[5]
"Twenty years ago," he said, "the idea held that inorganic chemistry was almost a dead science--dead in the sense of being apparently completed in many of its aspects, and that its records could be safely confided to the encyclopaedia.... A modified conception of life is now becoming co-extensive with the whole range of our experience. Even a simple inorganic crystal does not spring ready formed from its solvent, but first passes through phases of granulation and striation comparable with those which characterise the beginnings of vital growth. Metals exhibit in some respects phenomena similar to those possessed by organised beings. Thus, they show fatigue under long continued stress, and they recover their strength with rest. They are also susceptible to certain of the poisons which destroy organic life. Matter, broadly, is no longer merely dead masonry from which the edifice to shelter life { 75} is constructed, but also appears to be the reservoir of that energy which is developed, altered and drawn into vitality itself.... The indestructibility of matter bids fair to become relegated to the museum of outworn theories; and with it will probably go our present conceptions as to the conservation of energy."
It is clear, then, that the tasks awaiting the students of physical science are likely to be as arduous, and we may hope as full of reward, as they have been at any time in the past. Meanwhile, it does look as if there were truth in Mr. Balfour's remark that "Matter is not merely explained, but is explained away."[6]
[1] The weighing and measuring of the electron were first announced by Professor Thomson to the British Association meeting at Dover, in 1899.