Page:Popular Science Monthly Volume 24.djvu/732

714 Physics in Pictures. With Thirty Colored Plates for Ocular Instruction. By Theodore Eckardt and A. H. Keane. London: Edward Stanford. Text, pp. 20. 7s. 6d.

Common-Sense Binder. New York Asa L. Shipman's Sons.

Hints on the Drainage and Sewerage of Dwellings. By William Paul Gerhard. New York: William f. Comstock. 1884. Pp. 302. Illustrated. $2.50.

Lund and its Pent. By Francis A. Walker, Ph.D., LL. D. Boston: Little, Brown &, Co. 1883. Pp. 232. 75 cents.

A Bachelor's Talks about Married Life and Things Adjacent. By William Aikman. D.D. New York: Fowler & Wells. 1884. Pp. 273. $1.50.

The Philosophy of Self-Consciousness. By P. F. Fitzgerald. Cincinnati: E. Clarke & Co. 1883. $1.25.

Electricity, Magnetism, and Electric Telegraphy. By Thomas D. Lockwood. New York: D. Van Nostrand. 1883. Pp. 377.

For Mothers and Daughters: A Manual of Hygiene for Women and the Household. By Mrs. E. G. Cook, M.D. New York: Fowler & Wells. Pp. 392. Illustrated. $1.50.

Geological Survey of Alabama: Report for Years 1881 and 1882. By Eugene Allen Smith, Ph.D. Montgomery, Ala.: W. D. Brown & Co. 1883. Pp. 615, with Maps.

Second Biennial Report State Board of Health of Iowa for Fiscal Period ending June 30, 1883. Des Moines: George E. Roberts. 1883. Pp. 417.

The Relations of Mind and Brain. By Henry Calderwood, LL.D. Second edition. London: Macmillan & Co. 1884. Pp. 527.

Chemistry, Inorganic and Organic, with Experiments. By Charles Loudon Bloxam. From the fifth and revised English edition. Philadelphia: Henry C. Lea's Son & Co. 1883. Pp. 738. Cloth, $3.75; leather, $4.75.

First Registration Report of the State Board of Health of Iowa, for the Year ending October 1, 1881. Des Moines: George E. Roberts. 1883. Pp. 811.

The Field of Disease: A Book of Preventive Medicine. By B. W. Richardson, M.D., F.R.S. Philadelphia: Henry C. Lea's Son & Co. 1884. Pp. 737. Cloth, $4; leather, $5; Russia, $5.50.



Sub-aerial Decay of Rocks.—Professor T. S. Hunt publishes, in the "American Journal of Science," an elaborate paper on the "Decay of Rocks," in which he insists that recent geological studies afford evidence that a sub-aerial decay both of silicated crystalline and calcareous rocks has taken place universally and from the most ancient epochs, and that it was very extensive in pre-Cambrian times. He further insists that the materials resulting from this decay are preserved in situ, in some regions by overlying strata; in others by the position of the decayed material with reference to denuding agents; and that the process of decay, though continuous through later geological ages, has, under ordinary conditions, been insignificant in amount since the glacial period, on account of the relatively short time that has elapsed, and also, probably, on account of changed atmospheric conditions in the later time. The process of decay, he believes, "has furnished the materials for the clays, sands, and iron-oxides from the beginning of Palæozoic time to the present, and also for the corresponding rocks of Eozoic time, which have been formed from the older feldspathic rocks by the partial loss of protoxide bases. The bases thus separated from crystalline silicated rocks have been the source, directly and indirectly, of all limestones and carbonated rocks, and have, moreover, caused profound secular changes in the constitution of the ocean's waters. The decay of sulphureted ores in the Eozoic rocks has given rise to oxidized iron-ores, and also to deposits of rich copper-ores in various geological horizons." Finally, Professor Hunt maintains that "the rounded masses of crystalline rock left in the process of decay constitute not only the bowlders of the drift, but, judging from analogy, the similar masses in conglomerates of various ages, going back to Eozoic time; and that not only the forms of these detached masses, but the outlines of eroded regions of crystalline rocks, were determined by the preceding process of sub-aërial decay of these rocks."

"Colds."—The views of Dr. Page on the subject of "catching cold," published in the "Monthly" for January, having been sharply criticised as unsound and extreme, we give below an extract on the same subject from the London "Lancet," a scientific medical authority of the highest grade: "A person in good health, with fair play, easily resists cold. But when the health flags a little, and liberties are taken with the stomach or the nervous system, a chill is easily taken, and, according to the weak spot of the individual, assumes the form of a cold, or pneumonia, or, it may be, jaundice. Of all causes of 'cold,' probably fatigue is one of the most efficient. A jaded man coming home at night from a long day's work, a growing youth losing two hours' sleep over evening parties two or three times a week, or a young lady heavily 'doing the season', 