Our highest admiration must be for the discoverers; but we may do well to remind ourselves, from time to time, that to such men we are indebted not only for thrilling insight into the beautiful mysteries of nature, and for the withdrawal of the veil which shuts out from ordinary sight the august magnificences of nature, but also for the discovery of those principles which can be turned to the best practical account, ministering to us in our kitchens and bed-chambers and drawing-rooms and factories and shops and fields, filling our nights with brilliancy and our days with potencies, giving to each man the capability of accomplishing in one year what his ancestors, who lived in unscientific ages, could not have achieved in twenty; not only exhibiting the forces of nature as steeds, but also showing how they may be harnessed to the chariots of civilization.

To keep us in healthful gratitude to the men who, having turned away from the marts of the money-makers, have unselfishly set themselves to discover what will enrich the money-makers, and, content to live in simple sorts of ways, have sent down beauty and comfort into the homes of rich and poor, it is well to make an occasional résumé of the results of the work of useful scientists, and ponder the lessons of their single-mindedness.

FARADAY.

Few names on the roll of the worthies of science are better known through all the world than that of Michael Faraday, who was born in England in 1791 and died in 1867. Rising from poverty, he became assistant to Sir Humphrey Davy, in the Royal Institution, London, where he soon exhibited great ability as an experimenter, and a rare genius for discovering the secret relation of distant phenomena to one another, which gave him his skill as a discoverer, so that he came to be regarded, according to Professor Tyndall, "the prince of the physical investigators of the present age," "the greatest experimental philosopher the world has ever seen."

His greatest discoveries may be stated to have been magneto-electric induction, electro-chemical decomposition, the magnetization of light, and diamagnetism, the last announced in his memoir as the "magnetic condition of all matter." There were many minor discoveries. The results of his labors are apparent in every field of science which has been cultivated since his day. Indeed, they made a great enlargement of that field. His life of simple independence was a great contribution to the highest wealth of the world. He might have been rich. He lived in simplicity and died poor. It is calculated that, if he had made commercial uses of his earlier discoveries, he might easily have gathered a fortune of a million of dollars. He preferred to use his extraordinary endowments for the promotion of science, from which he would not be turned away by honors or money, declining the presidency of the Royal Institution, which was urged upon him, preferring to "remain plain Michael Faraday to the last," that he might make mankind his legatees.

While Faraday does not claim the parentage of the electric telegraph, he was among the earliest laborers in the practical application of his own discoveries, without which the telegraph would probably never have had existence. It was on his advice that Mr. Cyrus W. Field determined to push the enterprise of the submarine cable. His labors were essential to the success of the efforts of his friend Wheatstone in telegraphy. It was his genius which discovered the method of preventing the incrustation by ice of the windows of light-houses, and also a method for the prevention of the fouling of air in brilliantly lighted rooms, by which health was impaired and furniture injured. He discovered a light, volatile oil, which he called "bicarburet of hydrogen." It is now known to us as benzine, which is so largely employed in the industrial arts. Treated by nitric acid, that has produced a substance largely used by the perfumer and the confectioner. From that came the wonderful base aniline, which was not only useful in the study of chemistry, as throwing light on the internal structure of organic compounds, but has come also into commerce, creating a great branch of industry, by giving strong and high colors which can be fixed on cotton, woolen, and silken fabrics. It may be worth while to notice what gratifying beauty was provided for the eye, while profitable work was afforded to the industrious.

It is not to be forgotten that, whatever we have of magneto-electric light, in all its various applications, is due to Faraday's discoveries.

Faraday's distinguished successor, Professor Tyndall, in his admirable and generous tribute to his famous predecessor, says: "As far as electricity has been applied for medical purposes, it is almost exclusively Faraday's." How much of addition to human comfort that one sentence includes, who can estimate? And who can calculate the money-value to commerce in the production of instruments used in the application of electricity to medicine? Professor Tyndall continues: "You have noticed those lines of wire which cross the streets of London. It is Faraday's currents that speed from place to place through these wires. Approaching the point of Dungeness, the mariner sees an unusually brilliant light, and from the noble Pharos of La Hève the same light flashes across the sea. These are Faraday's sparks, exalted by suitable machinery to sunlight splendor. At the present moment (1868), the Board of Trade and the Brethren of the Trinity House, as well as the Commissioners of Northern Lights, are contemplating the introduction of the magneto-electric light at numerous points upon our coast; and future generations will be able to point to those guiding stars in answer to the question, what has been the practical use of the labors of Faraday?"

SIEMENS

One of the most useful of modern men was Sir William Siemens, who was born in 1823 and died in 1883. The year before his death he was president of the British Association, and was introduced by his predecessor, Sir J. Lubbock, with the statement that "the leading idea of Dr. Siemens's life had been to economize and utilize the force of Nature for the benefit of man." It is not our purpose to give a sketch of his life, or a catalogue of his many inventions, all of which were useful. It was his comprehensive and accurate study of the universe which led him to discover, as he thought, that it is a vast regenerative gas furnace. The theory has been that the sun is cooling down; but Dr. Siemens saw that the water, vapor, and carbon compounds of the interstellar spaces are returned to the sun, and that the action of the sun on these literally converted the universe into a regenerative furnace. On a small scale, in a way adapted to ordinary human uses, and by ingenious contrivances, he produced a regenerative gas furnace which so utilized what had hitherto been wasted that, in the last lecture delivered by Michael Faraday (1862) before the Royal Society, he praised the qualities of the furnace for its economy and ease of management; and it soon came into general use. It is probably impossible to calculate the amount of saving to the world due to his practical application of the theory of the conservation of force to the pursuits of industry. It has changed the processes for the production of steel so as to make it much cheaper, and so revolutionized ship-building. The carrying power of steel ships is so much greater than that of iron ships that the former earn twenty-five per centum more than the latter. So great a gain is this, that one-fourth the total tonnage of British ship-building in 1883 consisted of steel vessels.