When you have read all this about heating and ventilating two or three times over, these conclusions will begin to crystallize in your mind:—­

Open fires give the surest ventilation and the best cheer.

If stoves are used for economy, fresh air must be systematically admitted.

Furnaces are immensely useful to warm the bones of the house and as a sort of reserve force; but the heat they give is somewhat like a succession of January thaws.

If you begin to investigate you will discover a fearful amount of ignorance and indifference where you should find positive information, and the most discouraging obscurity or conflicting statements among those who profess to be wise in such matters.

LETTER XLI.

From John.

ETERNAL VIGILANCE.

MY DEAR ARCHITECT:  You did well to send the key to your puzzles, else I might have frozen to death before finding out how to keep warm.  But you’ve earned your discharge, which I forward herewith.  Now I’m going to send you some grains of wisdom, gathered during my experience in building, which you may distribute at your discretion among your clients.  When a man—­I don’t care if it’s Solomon himself—­undertakes to build a house, tell him from me, to wind up all other earthly affairs before beginning; wind them up so tight they’ll run for a year or two without any of his help.  Then turn over a new leaf,—­learn to get through breakfast before seven A.M., in order to be on the ground every moment, from the time the first spadeful of dirt is thrown out till the last touch of paint is put on.  You may make full-sized drawings for him of every stick and stone, write specifications by the yard, and draw up a contract that half a dozen lawyers can’t expound, there’ll still be a thousand little things that won’t be done as he wants them.

The openings in the basement wall somehow get out of place, an inch or two too high or too low, or at one side, then the windows over them will look askew.  The air-spaces in the wall will be filled up where they ought not to be, or left out where they ought to be filled; then the frost will go through one and the rats the other.  If he uses colored mortar, it will be too dark or too light, or too something,—­then he’ll be obliged to paint the whole wall.  The drains won’t be put in the right place, or they’ll pitch the wrong way; then he’ll have to dig out new ones.  The receivers for the stove-pipes will be forgotten or set in the ventilating-flues; then he might as well have no chimney.  The masons will drop bricks and mortar and trowels down the flues; then he’ll have to climb upon the roof with a brick tied to a rope and try to churn them out.  Just at the place where the flues ought to be plastered outside and in, against the floor and roof timbers, the masons can’t reach, and like as not they’ll turn a brick up edgewise if a joist happens to crowd; then his house will burn up and never give him any more trouble.