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280 Mr. Im Thurn had observed no animal life while he was upon the mountain; Mr. Dressel saw a few butterflies, all of a dark-brown and nearly black color. In the shallow basins a few specimens of a small black toad with a yellow spot on the throat were found. A third animal form was noticed in the moist earth attached to some plants which had been pulled up—a milliped. The fantastic shapes into which the sandstones have been formed, and the calmness of the scene, affected Mr. Dressel as they had Mr. Im Thurn.

Experience and Training in Mechanical Work.—To be a good mechanic, said Sir Benjamin Browne, at the recent meeting of the British Association, long training is necessary; and, above all, ability to distinguish good work from inferior work. A regular course of progress from one branch to another should be carefully followed, so as to teach every class of work up to the most difficult. In this the real interest of the employer is the same as that of the lad, viz., to learn every step thoroughly, and then pass on to something more difficult. The author contended that a long training in a manufactory is absolutely necessary, and this should be supplemented by theoretical and technical instruction. It would probably be a great gain to give a lad six or eight months of theoretical teaching after he is out of his apprenticeship. The old-fashioned system of apprenticeship, not much shortened, and with very slight modifications, is the only reliable method for either employer or mechanic to learn his business; but, as work has become more scientific and elaborate, it is necessary for any young man who wishes to excel to have a good theoretical and technical training in addition to his factory experience.

How Stone Implements were made.—Mr. Gerard Fowke, of Sidney, Ohio, has been studying the manner in which primitive man made his stone implements. Although the subject is one on which absolute knowledge can never be obtained, he has been able to reach some definite conclusions on it. Some of the material was obtained from extensive quarries in Coshocton County, and between Newark and Zanesville, Ohio, where the hills are seamed for miles with the trenches and pits left by the ancient diggers. To get the flint, the overlying stratum of earth, nine or ten feet thick, had to be removed, with wooden tools. The rock was then cracked by building a fire, and probably pouring water upon it, the process being repeated till the limestone was reached and a hole made large enough to work in. Other cracks were made by building a fire at the lower part of the ledge, and the split rock was detached. This work was sometimes carried on for several hundred yards. The stones were reduced to blocks of suitable size by stone hammers weighing, perhaps, two hundred pounds, and the shaping was carried on with hammers running, according to its stage and the quality of work desired, down to two ounces in weight. The finished object was smoothed and sharpened by rubbing it with sandstones. If a hole was wanted, it was drilled with a stick, cane-stem, piece of bone or horn, flint, or piece of sandstone, which was revolved in the hands, or twisted back and forth with the bowstring. This was not a speedy process. Dr. Rau worked at it experimentally for two years, and left his first hole not bored through. Yet some of the Amazon tribes spend the lifetimes of two men in drilling, with the flexible shoot of a wild plantain and sand and water, the bores of their tubes of rock crystal. Handles were fitted on in a rude way and secured by wrapping with sinew, which shrunk and bound them tightly; or, with the aid of gum. The fashioning of arrow-heads was a very delicate and curious work, requiring skillful manipulation, and was performed with stone hammers or chisel-points of deer-horn or wood.

Bellite.—The new explosive, bellite, was recently subjected in England to some very satisfactory tests of its safety and power. Letting a great weight fall upon cartridges composed of it, they were simply crushed into a hard mass. But when the crushed cartridges were afterward detonated by means of a fulminate, immense energy was developed. Again, when placed in the fire of a smith's forge, it was volatilized. The effect of exploding a three-ounce cartridge on the lid of a case containing bellite was simply to pulverize the wooden case and scatter the