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420 appears to be to remedy this difficulty by giving all the synonyms for each species under the head of the authorized English name, and by cross-references. The names of species are printed in capitals, those of doubtful species in Italics, and those of synonyms in ordinary type; and the name of the authority for the species is given, as far as possible, in italics. Well authenticated species are printed in large capitals; the synonyms follow in alphabetical order; and under species important varieties are printed in small capitals, with their synonyms. The synonyms under each species are divided into classes where that is necessary, and then arranged alphabetically for convenience in referring to them. The symbols representing the composition of the minerals are given according to the new system. The catalogue meets a felt want, for none of the standard works on mineralogy has a complete index.

worthy aim of this little book as defined in its preface is, "to elicit something clear and trustworthy" in regard to the effect of scientific discovery upon the probabilities of a future life. The author considers that science has been misinterpreted, especially concerning "the existence of God, the reality of the soul and its independence of the physical brain," and she proceeds to liberate it from misconception. The actuality of things unseen is evinced by the invisible rays of light, sounds made audible by the microphone, the phenomena of radiant heat, and molecular motion. The indestructibility of matter and the conservation of energy give reassurance of transformation, while the all-pervading, luminiferous ether "makes the universe seem one and homelike "! Within closer limits two uses are found for this ether: one as material upon which memory impressions may be made; the other, as the substance of the psychic body. Nature hints at continuance in the resurrection of the spring-time, and the fragmentary character of human life implies future completion, which, it is represented, may take place in other worlds than ours. We may yet remain "in the stream of evolution" and find an abiding-place without question of room, for, "if the planets fail us, there are all the hosts of the fixed stars." The nature of death and disposal of the dead are discussed, and cheerful views of our departure from earth are urged. Authorities are given with great impartiality from Prof. Tyndall to the Tonga Islanders, and science, like a veritable Sindbad, is made to sustain a multitude of inferences. Altogether, it must be said, this search for scientific confirmation of the hope of a hereafter is more suggestive than satisfying.

essays in this book were prepared in 1888 in answer to an offer of prizes by the periodical, The Metal-Worker, for the best methods of heating a house, plans and elevations of which were given. Three systems of heating—by steam circulation, by hot water circulation, and by hot air—were recognized in the competitions; and provision was made for the consideration of combination plans. The results of the competition were very successful, both in the number and character of the essays received and the attention they attracted. The essays in this book are reprinted from the journal in which they were first published; and to them are added summaries derived from very careful study of the competitive efforts. The papers are arranged under four different heads, namely: 1. Combination Systems, two essays—one on Steam and Warm Air, and one on Hot Water and Hot Air. 2. Steam-heating Systems, four essays. 3. Hot-water Circulating Systems, three essays. And 4. Hot air Systems, six essays. The papers indicate wide ranges of practice; and it is believed that, taken altogether, the fifteen essays present a better idea of current practice in house-heating than can be found anywhere else. All the systems proposed are adequately illustrated.

large volume is devoted mainly to describing the mineral resources of the