Page:Popular Science Monthly Volume 42.djvu/224

210 When it is to be set up, the three trucks, the length of which is equal to the width of the building, are brought up so as to be parallel in line and a few metres distant from one another, and are arranged so that their floors, which are to form part of the floor of the building, shall be on a level. Light T-shaped joists of iron are stretched across the intervals, supported by trestles when necessary, to receive the paper panels completing the floor. The other details of the structure are substantially as described by M. Ratoin. The interior of this building is entirely satisfactory, without visible framework, and without posts to interfere with the arrangement of the beds or with the circulation of the air. The walls, and the ceiling, which is inclined according to the inclination of the roof, are closely jointed and varnished, and consequently easy to wash and disinfect. The only open joints are the vertical couplings, which can be inspected and cleansed by simply taking them apart. The windows are of wire gauze covered with a transparent coating so as to avoid the inconveniences of glass. Ventilation is effected through holes bored at the angle of the ceiling and the wall.—. P. S. M.]

We do not purpose here to review all the new applications that have been made of paper, but have intended only to take notice of some of the principal ones, and to call attention to some of the improvements that have been made in them. To the other uses—in wagon-wheels, barrels, horseshoes, etc., mentioned in the beginning of this article—we may add a notice of the experiments that have been made in the use of paper in the manufacture of some articles of furniture, such as tables and folding chairs, the principal advantages of which evidently lie in their lightness. These experiments have been timid enough; but no long time will elapse before paper, which already has its masons and its carpenters, shall also have its cabinet-makers.—Translated for The Popular Science Monthly from La Nature.

analyses of the air of larger towns, made by a committee of the British Association for the Advancement of Science, and reported by Mr. G. A. Bailey, show: 1. That in clear, breezy weather the amount of sulphurous acid is less than one milligramme per one hundred cubic feet of air. 2. That in anti-cyclonic periods it rises very considerably, and in times of fog, maxima of thirty-four and fifty milligrammes have been recorded for the worst districts of Manchester and London respectively. 3. That wherever an open space or a less densely populated area occurs there is a very marked diminution in the amount of impurities in the air. 4. That an increase in the amount of sulphurous acid is accompanied by at least as large an increase in the amount of organic impurities in the air. 5. That smoke, promoting as it does the formation of fog, and preventing free diffusion into the upper stratum of the air, must be regarded as the principal cause of the impure state of the atmosphere in large towns.