86o 



THE POPULAR SCIENCE MONTHLY. 



copper occur. In these beds the copper is 

 classed as stamp rock, in which the metal 

 is contained in fine particles and is separated 

 by crushing ; " barrel work," or the pieces 

 of copper that are large enough to be de- 

 tached 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 rock from the copper to 

 secure the latter. When they came upon 

 mass copper they were compelled to abandon 

 it after hammering off projecting pieces, be- 

 cause 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, be- 

 cause 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 min- 

 ing proper, as there were no shafts or tun- 

 nels or underground workings. 



Feeding Value of Tree Leaves. Exper- 

 iments 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 con- 

 siderable 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 feed- 



ing 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 car- 

 bohydrate 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 sum- 

 mer months ; and in September the wood pro- 

 duction of the trees would not be prejudiced. 



Gilbert White's Character. The Sel- 

 borne Society, of London, celebrated the 

 centenary of the death of Gilbert White, 

 June 24th, by making a pilgrimage to Sel- 

 borne, 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 culti- 

 vated, and of wide classical attainments and 

 accomplishments. He was not only an ob- 

 server of Nature, but one who prepared him- 

 self for observation by the best mental culti- 

 vation. No one could read his book without 

 seeing his remarkable faculty of observation, 

 and the constant aim at exactness and ac- 

 curacy, 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 pro- 

 duced 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 mem- 

 ory. 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 es- 

 pecially 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 under- 



