Gold, silver, lead, iron, tin, copper, and other metallic ores are there in abundance, and afford the student the most ample opportunity for study. In the collection of semi-precious or valuable stones there is a bewildering array. We find the topaz of all shades; we find rubies, emeralds, beryls, amethysts, agates, turquoise, onyx, garnets, aqua-marines, malachites, marbles, lapis lazuli, porphyries, and other stones in endless variety. As an illustration of the great variety of the mineral products of Russia, let me mention a little circumstance. On my desk, and lying before me as I write, is a paper weight I brought home from Siberia. It is a small mosaic, perhaps three inches by five, and contains no less than twenty-one kinds of variegated marbles from the Altai mountains. One piece is white, and another is nearly black, and there is great variety between the two extremes. Almost the only mineral products not known to exist in Russia is diamonds. They have been found in a few instances, but in very small numbers, and under circumstances that led to a strong suspicion that the places of discovery had been “salted.” [Sidenote: MINING SCHOOL AT ST. PETERSBURG.] In order to facilitate the study of the pupils in this school of mines, and make it as practical as possible, all the machinery and apparatus used in a mine has been arranged in an immense museum—some in the form of models, and others of their full size. Great mechanical skill has been displayed in the preparation of this machinery; whether in the shape of models or of full size, the working is perfect, and a student can easily understand from them the labor of the miner, and its result. Underneath the immense building there is a reproduction of one of the mines at Perm, one of the cities of the Oural mountains. The utmost care has been taken to make the reproduction perfect. You visit the place exactly as you would visit a real mine, and you are shown through it by the light of torches. You have the same temperature that you would have in the mine of which this is a copy, and the same kind of atmosphere. The character of the earth, the changes of color, the succession of layers of earth, rock, and ore, the machinery, the tools of the workmen, all lead a visitor to suppose he is really in a mine, and that the actual work has only been suspended a few hours while the laborers have been allowed a half holiday. The great mining centers of Russia are in the Oural and Altai mountains, especially the former. The wealth of the Ourals in minerals was almost unknown until the time of Peter the Great, when he sent some engineers to make an examination. Previous to that time some gold had been found, and brought to Moscow; and it was known that the former rulers of the kingdom of Kazan derived much of their wealth from the gold mines.