Page:Popular Science Monthly Volume 43.djvu/880

860 copper occur. In these beds the copper is classed as stamp rock, in which the metal is contained in line particles and is separated by crushing; "barrel work," or the pieces of copper that are large enough to be detached from the rock without stamping, which are shipped in barrels; and mass copper, or the very large pieces. All this copper shows as such in the rock, and the ancient miners had only to follow down a promising outcrop showing "barrel work" for a few feet, and hammer away the lock from the copper to secure the latter. When they came upon mass copper they were compelled to abandon it after hammering off projecting pieces, because they had no tools for cutting it up and removing it. Several instances of this sort have been found. The ancient mines were not mines in the strict sense of the word, because they were not underground workings, but merely shallow pits or trenches, and sometimes excavations in the face, of the cliffs. At the time modern mining began they had become mere depressions in the ground. All these workings when examined contained countless stone hammers or mauls, a few wooden shovels, remains of wooden bowls for baking, birch-bark baskets, and some spear or lance heads, and other articles of copper. Opinions and evidence vary as to the age of the operations. Modern miners would regard the whole system as nothing more than prospecting work, and not raining proper, as there were no shafts or tunnels or underground workings.

Feeding Value of Tree Leaves—Experiments on the feeding value of the leaves of trees, made by M. C. H. Girard, point to them as an available source of nutriment for cattle, particularly in times when hay and grain are scarce. The author has determined the content of nitrogenous matters in a considerable number of species. It ranges from eight per cent in the willow and alder to from three to four per cent in the plane, birch, and pine. Out of twenty-one kinds of leaves studied, nineteen possessed more nitrogenous matter than meadow hay, and more than half of them were superior to the hay of the best leguminous plants. Some are of extraordinary richness, the common acacia, for example. M. Girard was able, from his analyses and from direct experience in feeding sheep, to draw the conclusion that the leaves have a feeding value comparable to that of lucern. They are also superior in the proportion of fat matters and other carbohydrate principles to that of water. Leaves taken from various heights of the trees and from trees of various ages show but little variation in composition; and, putting aside the periods of youth and of extreme old age, the richness of the leaf in nutritive value remains almost stationary. Consequently, crops can be gathered during the three summer months; and in September the wood production of the trees would not be prejudiced.

Gilbert White's Character.—The Selborne Society, of London, celebrated the centenary of the death of Gilbert White, June 24th, by making a pilgrimage to Selborne, where the earl of that ilk spoke to the memory of White. He said that the impression which most people had formed of White from his book was that he was a man of excellent natural abilities, strongly cultivated, and of wide classical attainments and accomplishments. He was not only an observer of Nature, but one who prepared himself for observation by the best mental cultivation. No one could read his book without seeing his remarkable faculty of observation, and the constant aim at exactness and accuracy, together with a good deal of humor. Nor could any one help being struck with the modesty and simplicity of his character. His simplicity, which contributed a very great charm to the book, every now and then produced even a sense of amusement. The speaker was visited, in 1872, by Mr. W. M. Evarts, who, like most other cultivated Americans, was acquainted with White's book, and had a great regard for his memory. One day, when driving, the Sussex downs were pointed out to Mr. Evarts, who burst into laughter, remembering a passage in which White referred to the downs as "a vast range of mountains." His shrewdness of discernment was a most valuable gift, and he loved all God's creatures, but perhaps especially birds. By this he reminded one of two great men. The one, mythical, was Melacampus, who rescued and brought up some young serpents. One day, when he slept, the serpents nestled round his head, and when he woke he found he could