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Rh difficult to see how the classroom can prove as good a ground for this diversion as the library. The provincial note of the book is reached in the sixth chapter, Demands made by the Community upon Her. It seems obvious to us that if woman had done only what the community required of her, she would never have gone to college, and that, having gone, it is unlikely she will thereafter order her ways according to Mrs. Grundy. Such a standard is surely not an ethical goal for either man or woman, who needs to do right for right's sake, even in the face of the community.

author aims in this volume to give credit to every one who has contributed even in the slightest degree to the development of thought in the field of electrical science and art. The great ideas and inventions by which progress is marked are arranged in three type groups: Immature or incomplete; untimely and therefore unfruitful; and fruitful, because mature and timely; of which the first class, though having but little visible influence, may at times be of value, because of their tendency to direct thought along certain channels, thereby they become forerunners of more important ideas. The second class have to wait for recognition and effect, but eventually contribute their force to the advancing impulse; while the third class are fruitful at once. The first enunciation of ideas concerning electricity is traced back to the Greek philosopher Thales, who experimented with the attraction of a piece of amber that had been rubbed. He was much before his time, for no advance was made on his experiment till near the close of the sixteenth century, when Dr. Gilbert showed that powers of attraction and repulsion are developed in several other bodies by rubbing them. Stephen Grey, in 1729, first pointed out the distinction between conductors and non-conductors of electricity. The power of wires to conduct the electrical force to a distance attracted attention and excited inquiry, in the course of which Watson, in 1747, erected conducting lines several miles in length, and used the earth as a return conductor. He was succeeded by Franklin, whose experiments arc familiar, and were followed by the rapid development of electrical discovery which has not yet slackened. The invention of the electric telegraph, with the discoveries that made it possible and led up to it, and of the telephone, are reviewed in a very clear and comprehensive manner. The application of electricity as a motive power and light producer was first made commercially practicable after the invention of the Gramme dynamo. Since then it has been rapidly extended, and is likely to become general all over the earth, and as to all kinds of machinery. Still more wonderful expansions of electricity seem to be foreshadowed by the discoveries of Hertz, Tesla, and other workers of the day. As possible features of this future expansion, Mr. Houston dreams of a cheaper means for the production of electricity than is possible by the present method; perhaps producing it directly from the burning of coal; the entire replacement of the steam engine by the electric motor; the successful solution of the problem of aërial navigation, effected, possibly, by means of the electric motor, and being rendered possible as a result of improvements in the economical production of electricity; the replacing of the present electric light, with its preponderance of useless and injurious low heat rays, by some species of electrically produced light which shall possess a smaller proportion of the useless heat rays and a larger proportion of the desired light rays; a more intelligent means than are now adopted in the therapeutical applications of electricity to the curing of diseases; electrical transmission of pictures; electrical preparation of roadbeds by vitrifying the clay or soil in situ; and "an apparatus for the automatic registration of unwritten, unspoken thought, and its accurate repetition at any indefinite time afterward."

are glad to see the publication of Science resumed. There certainly is room, as Prof. Newcomb well observes in an editorial address to its readers, for a journal