Page:Popular Science Monthly Volume 42.djvu/545

 Rh of clay is followed by an account of the manufacture of bricks, tiles, drain pipes, chimney pots, etc. Slate finds its proper place hereabouts.

Such stuffs as marble, granite, sandstone, and plaster (stucco) may be now described.

The chief metals used in house construction or in house furniture are iron, lead, zinc, copper, tin, and mercury, and their derivatives, such as brass, zinc plate, tin plate, and so on. And, perhaps, the only stuffs still demanding consideration are glass, glue, whitewash, litharge, and putty.

Now, all these stuffs should not only be seen, they should be handled by the pupils, and such processes as the slacking of lime, the setting of mortar and of plaster, the baking of clay, and the reduction of some of the metals from their ores, should be shown, as can easily be done by means of the materials and a few pieces of apparatus before you.

It is thus seen that I adopt the plan, which I think is the soundest one, of not attempting to generalize or philosophize until the child has got something to generalize from. But such generalization must not be delayed too long; for it is of incalculable help to the pupil in his further studies.

Accordingly, I would here or hereabouts introduce him to that truly awful revelation that there are on the earth, as far as we can search; in the earth, as far as we can dig; ay, and throughout the universe as far as we can see, but a limited number of prime stuffs—the elements. To my mind two men are in no sense on the same intellectual level whereof the one can and the other can not tell you of what elements familiar things consist. The latter may be intelligent, possibly he is well-meaning; intellectually he is a savage. Such savages abound in all strata of our commonwealth. Such savages are dangerous. We must not kill them; we are not even permitted to teach them. Let us at least catch and civilize their children, both for their own sakes and ours.

The conception of the elements leads at once to air and that type of chemical uniting called burning. Much time spent in a careful study of fire, flame, and water would be well spent indeed. Practically, and returning to our scheme, I find it far best for educational purposes to secure such generalization at about this point. The pupil can now understand something about wood, the last of the stuffs considered in the building of a house.

Such knowledge brings us at once to the heating and lighting of the house, and so to the manufacture of charcoal, the formation of peat, and the making of coal gas. The methods of obtaining a light lead to the interesting and instructive subject of matches, and the stuffs of which they are made.

Our next chapter might properly include the finishing and