Lectures on Practical Geology. By Professor D. T. Amsted. (Hard.
wicke.)—Professor Ansted has some difficulty in descending to the
level of the unlearned, otherwise this would be a very useful volume. Some knowledge of geology and chemical terms is required, with this, and steady attention, any one may arrive at a very respectable acquaint- ance with the nature of soil; the conditions of a good water supply, the laws that determine the formation of mineral deposits, and the process of mine-working by the help of these lectures. They form just the sort of book that an educated man requires who is conscious of a deficiency in a special branch of science. We are glad to find that Professor Ansted, though serious, is not an alarmist on the coal question. He es- timates our annual consumption at 100,000,000 tons, with a waste of a fourth more in the extraction: but there are 6,000,000,000 still available in the Newcastle field alone, 4,000,000,000 in South Lancashire, and other inferior supplies in Yorkshire, Shropshire, and South Staffordshire, and when these fail there is the great South Welsh coal-field to fall back en, "the largest and most important in the British Islands."