The weather strip must be put on by the experts from the manufacturers of the brand of weather strips that you buy. _Do not call in your favorite carpenter or plumber, for he cannot do it right._ The putting on of weather strips is a science in itself. They must be put on so as to insure a uniform efficiency during the inevitable warpings, shrinkings and swellings of the window. The windows have to be conditioned carefully because the stripping must be so fixed that it cannot be removed, if necessary to do anything to the window itself afterwards, such as fitting new pulley cords, etc. Every window and door offers different problems, so an expert must apply the strips to your window and door. This is not a commodity that a baby can affix--it’s a man sized job. PURCHASING Remember the weather stripping that you buy should last as long as the life of your house. For this reason the all metal kind is the best to buy. The metal and cloth are efficient as long as they last, and so are other combinations; but they do not last long enough. You must get a longevity insurance. They must be made of non-rusting, non-corroding materials such as bronze, copper, zinc or brass manufactured to a high degree of dependability, and subjected to the most rigid inspection and tests for accuracy, thereby awarding the buyer a rich guarantee. Find out from users of the brand you think you will buy, before you buy, and see what they say and what their experience has been. Weather strips can be put on any opening, and should the purveyor you speak to say this or that opening cannot be properly stripped, that is your cue for seeking elsewhere. Buy only from established makers, who will be in business for years--because in twenty or thirty years you might want a window adjusted. Early in this article mention was made of the saving in fuel by Uncle Sam. Professor Allen, of the Research Laboratory of The American Society of Heating and Ventilating Engineers, in a letter to the writer said: “Roughly with ordinary good house conditions we can say that the air in a room changes every hour due to leakage around windows. With good weather strips you reduce the leakage very considerably. Of course, this depends upon the type of construction in the house. Some years ago I installed a complete system of weather stripping in an entire institution and we roughly estimated that the saving of fuel was about 15%.” Since then other tests have been made to bring the percentage of saving of fuel from 15% to 40%. When you think that a window shade keeps in 19.2% of warm air, think what the fitted metal and interlocking strips can do.