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Rh  presentation of the subjects under consideration that has characterized Prof. Foster's former work, and has made this in the past one of the best works on physiology that we have; and the incorporation of the more recent discoveries in that science in this volume sustains its high standard. The only thing that detracts from this volume is the omission of an index.

book is described in the subtitle as "Some Account of Nature's Crops, and how they are grown." It maintains the proposition that "the whole earth is one great farm or garden, almost everywhere covered with vegetation, and bringing forth crops of the most luxuriant and varied kind"; and that Nature farms in ways of her own, on a large scale and without fuss, with a tillage of the most thorough kind, though it may be carried on without steel plows, and so quietly as to escape our notice. "There are vast pasture-lands here, there are extensive forests there; there are woods, jungles, heaths, moors, downs, but they have, all been planted; and the soil was prepared in the first instance, and has been renewed since, by laborers who are not less truly deserving of the name of laborer than the plowman, though they do not work with his implements." Of these laborers we are introduced first to the "pioneer laborers"—the gases of air and water—"which wear away the very hardest rocks by degrees"; then to the "soil-makers"—the lichens which sprout in the débris of the weathered rocks, and the roots of which, with those of the plants that follow them, continue the work done by air and water; to the "soil-carriers"—the rivers; the "soil-binders"—grass and plant roots; and the "field laborers"—worms and burrowing insects and animals, which loosen the soil; the work of which in the field particularly under view is graphically described. The work of water and roots, and the reason for deserts, are more fully considered. The office of plants in drawing food from the soil and leaving it there when they die in a more assimilable condition, and leaves and their work, are described—the influence of climate, "blossom and seed," the meaning of fertilization and the work of insects in assisting the process, and the methods of diffusion, are explained; and chapters follow on the Chances of Life, Friends and Foes to Plant Life, Nature's Militia, and Man's Work on the Farm. The whole is a successful attempt to present knowledge of the phenomena and processes of growth in an attractive form, to which a few excellent illustrations lend additional grace.

In this treatise the use of the blowpipe in analytical and determinative work is treated with great fullness. The chapter on appliances and flames is fully illustrated. This is followed by descriptions of the several modes of examining minerals, including some operations with wet reagents. A dozen pages of tables giving reactions for the oxides of earths and metals constitute Chapter III. Some seventy pages are devoted to prominent blowpipe reactions for the elements and their principal mineral compounds, arranged alphabetically under the names of the elements. Special suggestions as to the treatment of alloys, metallurgical products, and pigments are given; and these are followed by a systematic method of qualitative analysis before the blowpipe. Over a hundred pages of determinative tables are given, in which more than four hundred species of minerals are described. In these tables seven chief divisions are made—namely, metallic malleable minerals, flexible minerals, sectile malleable minerals, minerals with and those without metallic luster, earthy minerals, and hydrocarbon compounds. The methods of Prof. Richter, of Freiberg, have been largely followed in this manual, the author having been one of Richter's pupils.



Annual Report of the Postmaster-General to June 30, 1892. Washington: Government Printing Office.

Bates, Henry Walter. The Naturalist on the River Amazon. New York: D. Appleton & Co.

Becker, George F. Finite Homogeneous Strain, etc., of Rocks. Rochester, N. Y., Geological Society of America.

Blue and Gray. Monthly. January, 1893. Philadelphia: Patriotic Publishing Company. $2.50 a year.