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454 signs of the times, that the civilized nations of Europe and America are awakening, slowly but surely, to this truth. The civilized world is learning, thank God, more and more of the importance of physical science; year by year, thank God, it is learning to live more and more according to the laws of physical science, which are, as the great Lord Bacon said of old, none other than "Vox Dei in rebus revelata"—the voice of God revealed in facts; and it is gaining, by so doing, year by year, more and more of health and wealth; of peaceful and comfortable, even of graceful and elevating, means of life for fresh millions.

If you want to know what the study of physical science has done for man, look, as a single instance, at the science of sanitary reform; the science which does not merely go to cure disease, and shut the stable-door after the horse is stolen, but tries to prevent disease; and, thank God, is succeeding beyond our highest expectations. Or look at the actual fresh amount of employment, of subsistence, which science has, during the last century, given to men, and judge for yourselves whether the study of it be not one worthy of those who wish to help themselves, and, in so doing, to help their fellow-men. Let me quote to you a passage from an essay urging the institution of schools of physical science for artisans, which says all which I wish to say and more:

"The discoveries of voltaic electricity, electro-magnetism, and magnetic electricity, by Volta, Oersted, and Faraday, led to the invention of electric telegraphy by Wheatstone and others, and to the great manufacturers of telegraph-cables and telegraph-wire, and of the materials required for them. The value of the cargo of the Great Eastern alone in the present Bombay telegraph expedition is calculated at three million pounds sterling. It also led to the employment of thousands of operators to transmit the telegraphic messages, and to a great increase of our commerce in nearly all its branches by the more rapid means of communication. The discovery of voltaic electricity further led to the invention of electro-plating, and to the employment of a large number of persons in that business. The numerous experimental researches on specific heat, latent heat, the tension of vapors, the properties of water, the mechanical effect of heat, etc., resulted in the development of steam-engines and railways, and the almost endless employments depending upon their construction and use. About a quarter of a million of persons are employed on railways alone in Great Britain. The various original investigations on the chemical effects of light led to the invention of photography, and have given employment to thousands of persons who practise that process, or manufacture and prepare the various material and articles required in it. The discovery of chlorine by Scheele led to the invention of the modern processes of bleaching, and to various improvements in the dyeing of the textile fabrics, and has given employment to a very large number of our Lancashire operatives. The discovery of chlorine has also