The thinnest paper serves to keep the air quiet.  A newspaper laid on a bed acts much as a coverlid to keep a film or layer of air quiet, and thus less heat escapes from the bodies of the sleepers.  If paper is pasted up over the cracks of a house, or of a barn or stable, or under the joists of a house floor, it has just the same effect.  Every person who keeps animals will find it a wonderful and paying protection to them, to put against the walls one, two, three, or more layers of newspapers during cold weather.  If a person in riding finds his garments too cool, a newspaper placed under the coat or vest, or under or over the trousers, even if only on the side next the wind, will do a great deal to check the outflow of heat, and keep him warm.  Two or three thicknesses of newspaper crumpled a little, and put under the coat or overcoat, are almost as effective in keeping in warmth as an extra garment.  A slight crumpling keeps them a little separate, and makes additional thin layers of air.

Further:  Heat does not pass through films of still air.  Fibrous woolens, furs, loosely woven cotton, down, and the like, contain a great deal of air confined in the meshes, and are therefore excellent conservers of heat.  Double walls of stone, brick, or wood, or even of wall or roofing paper, double glass, double layers of anything that will have thin layers of still air between them, prevent the escape of heat greatly.

* * * * *

THE SCIENTIFIC AMERICAN

ARCHITECTS AND BUILDERS EDITION.

$2.50 A Year.  Single Copies, 25 Cts.

This is a Special Edition of the SCIENTIFIC AMERICAN, issued monthly—­on the first day of the month.  Each number contains about forty large quarto pages, equal to about two hundred ordinary book pages, forming, practically, a large and splendid MAGAZINE OF ARCHITECTURE, richly adorned with elegant plates in colors and with fine engravings, illustrating the most interesting examples of modern Architectural Construction and allied subjects.

A special feature is the presentation in each number of a variety of the latest and best plans for private residences, city and country, including those of very moderate cost as well as the more expensive.  Drawings in perspective and in color are given, together with full Plans, Specifications, Costs, Bills of Estimate, and Sheets of Details.

No other building paper contains so many plans, details, and specifications regularly presented as the SCIENTIFIC AMERICAN.  Hundreds of dwellings have already been erected on the various plans we have issued during the past year, and many others are in process of construction.

Architects, Builders, and Owners will find this work valuable in furnishing fresh and useful suggestions.  All who contemplate building or improving homes, or erecting structures of any kind, have before them in this work an almost endless series of the latest and best examples from which to make selections, thus saving time and money.