LETTER XXXVIII.

From the Architect.

WHEN THE DOCTORS DIFFER.

DEAR JOHN: Your economical reasons for using shingles would justify cheap jewelry and rag carpets. Try to be consistent. I should object to slate on a log-barn or shingles on a stone-house. I hope you furnished your honest carpenter with a stout jack-knife, and required him not only to lay the shingles right side up, but to lay the upper ends close together, leaving them apart at the butt. Gutters are troublesome truly, but often indispensable; there is no resource but to have them thoroughly made. Poor ones are worse than

The problem of warming and ventilating is easily solved for those who desire its solution sufficiently to make the necessary appropriations. One quarter of what is commonly spent for vanity and deceit will be ample. Most men and women, at least the unthinking, prefer fashionable show rather than health! A fearful statement, but sadly true. There is doubtless more danger from impure air than from cold. Our senses warn us quickly of the latter; the prompting of knowledge is needed to guard us against the former,—of a practical knowledge unfortunately rare. Men, women, and children are

Let me give you first a suggestion for summer ventilation. Did you ever shingle the south side of a barn on a calm, hot, sunny day in July, thermometer at ninety degrees in the shade? Did you ever lay your hand on a black slate or tin roof exposed to the direct rays of a midsummer sun? Have you ever, at the close of some hot, labor-spent day in August, sat out of doors until the evening air became de

Now, there is no good reason why the rooms immediately under the roof of a house should be any more uncomfortable on account of heat than those of the first story. Nay, more, by the simplest application of common-sense, these upper rooms may be so coolly ventilated that the hotter the sun pours his rays upon the roof the more salubrious shall be your palace in the sky. And this I call a triumph of genius, making the seemingly destructive wrath of the elements to serve and save us.

M. Figuier tells us with just how many hundred thousand horse-power the sun, by the caloric of its beams, operates upon the surface of the earth. I cannot tell precisely how much

And this is the way to cause the heat of a burning sun to cool the attic chamber: Make the space between the rafters on the sunny sides of your building as smooth and unobstructed as possible. Arrange openings into the outer air at the lower end of each, simple or complex, according to your taste and ability. Provide also means for closing the same in cold weather. Be sure that these spaces, or flues, are enclosed either by lath and plaster, or by smooth boards, quite to the highest part of the roof, whether your rooms are finished to the top or not,—and provided with an abundant outlet at the top. This may also be as simple as the

Now, do you not see that as soon as the sun has warmed the flues, there will be a stiff breeze blowing, not over the roof, but really between the roof and the house, and the hotter the sun the stiffer the breeze; in the words of one who has tried it,—"a perfect hurricane." That is, the lath and plaster, or sheathing, which forms the inner roof, is shaded by a canopy of slate, shingles, or tin, and fanned by a constant breeze as cool at least as the outer air. But we can do vastly better than that. Instead of opening the

Let me remind you, under the head of general principles, that there is no such thing as "suction." Of course, you know it when you stop to think, but bear it in mind, and wherever the motive-power seems to be applied on which you rely to lift the column of air, remember that if raised at all it must be raised from the bottom. Maybe you will discover room for a moral here.

This summer ventilation is simple enough, and relates rather to comfort than to health. The great question in building, for New England and similar climates, is, indeed, how to keep our houses warm, and, without great expenditure of fuel, have a constant change of air. As you suggest, we have learned that wood costs eight or ten dollars a cord instead of the mere labor of cutting and hauling; hence we have shut the

Yet we build and furnish more wisely than our ancestors. They ventilated because they couldn't help it, couldn't afford to build as we do, and could afford to burn an acre of woodland every year.

It is no light task you have set me preliminary to an honorable discharge. Next to theology and government finance there is no subject on which the doctors differ and dogmatize as in this matter of warming and ventilating, most of them preferring that the universe should suffocate rather than their pet theories and furnaces be found wanting. (I'm not speaking of the theologians.)

Thus far, except the old fogies who don't believe in ventilation, we can all travel together harmoniously. Now our way divides, the doctors begin to differ, and the patients begin to die.

The first fork is at the two modes of warming, direct and indirect. The former includes stoves of all sorts,—sheet or cast iron, porcelain, soapstone, brick or pottery, box or cylinder, for wood or coal, air-tight, Franklin, "cannon," or base-burner, parlor cook or kitchen cook, charcoal basin, warming-pan or foot-stove,—anything in which you can build a fire. It includes open grates and fireplaces, ancient or modern, large

By the indirect mode it is enclosed in a chamber more or less remote, commonly called a furnace, and made of brick, sheet-iron, or wood lined with tin. Into this chamber cold air is admitted from some source, and escapes by its own levity, usually through tin pipes, to the rooms where the heat is needed. Sometimes it is driven out by mechanical means.

The advocates of the latter indirect mode claim for it many advantages. It is apparently clean.

The objections are less numerous but more weighty. The liability to imperfect construction and careless management often makes a furnace, especially a cast-iron one, a savor of death unto death rather than of health and comfort; also, when we are warmed by air thrown into a room at a high temperature, and dry at that, a greater degree of heat is necessary for comfort than if our bodies and clothing absorb heat from a radiating surface. The furnace, in short, compels us to breathe an atmosphere highly rarefied. We have the most careful and competent authority for believing this to be gravely injurious.

Now you may stop and think. Next time you shall have the conclusion of the whole matter.