Page:Popular Science Monthly Volume 91.djvu/122

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��Popular Science Monthly

��A Silo Roof Which Opens Like an Umbrella

A ROOF built like an urn brella is the ingenious de- vice of a manufacturer of ap- pliances for silos. It has this advantage: the structure can be filled five or six feet above the level of the walls; as the ensilage gradually settles, the roof will close down upon it automatically. This eliminates the need of a second filling of the silo after settling, and saves a good deal of labor and time.

The silo roof is constructed of triangular sections of galvanized iron, which are joined by sections of tenting. When the roof is open it. forms a continuation of the cylindrical walls of the silo, and as it settles upon the contents the triangles of metal join snugly. By an arrangement of joints that overlap, a weather-proof cover is formed. Within this are the sec- tions of canvas, which are likewise protected from the elements.

The supports that hold the roof to the upper wall of the silo are of wrought iron, and are so narrow that they offer little resistance to the wind. By pulling on a rope suspended through the center of the structure down to the floor, a single man can open the umbrella.

The roof can be attached to silos of concrete, metal, wood or tile. It is made in diameters of eight to seventeen feet.

����By pulling a rope one man can easily spread the umbrella roof

��The United States Armies Are Pre- paring to Fight Vermin and Germs

CLOTHING disinfectors of a portable type similar to those in use in Europe have been pur- chased by the United States Army. The outfit consists of a five-horse- power upright boiler connected by piping with a cylindrical chamber about six feet long and three feet in diameter. The rear end of this jacketed chamber is provided with a door that can be hermet- ically sealed. A rack for clothing slides into the chamber, while smaller articles are laid on a

��grating where they may be steam-soaked. The steam is generated in the boiler at about eighty pounds pressure. Suitable valves are provided to reduce this pressure to ten pounds when it enters the chamber. When the jacket about the chamber is thor- oughly heated, the articles to be disinfected are placed in the rack, which is then pushed into the chamber. The door is closed and made steam tight. When the temperature within the chamber has risen sufficiently, an exhauster is opened until the gage shows about fifteen inches of vacuum. Then a small amount of steam is allowed to enter the chamber. Following this, the ex- hauster again is opened until fif- teen inches of vacuum is indicated. Steam is then allowed to enter the chamber until the temperature within it rises to two hundred and thirty-eight degrees F. The steam is allowed to circulate through the chamber during the period of ex- posure. It is then cut off, and the exhauster draws off steam and vapor. After a short drying period the door may be opened and the clothing removed.

When using formaldehyde gas as a disinfectant in the apparatus the jacket is brought to a tempera- ture of eighty degrees F. ; the clothing then is placed in the chamber and a vacuum of fifteen to twenty inches obtained. When a temperature of ninety degrees is reached, the gas is admit- ted.

���A disinfector for our Army. It can handle fifty uniforms and kits in forty minutes ridding them of all germs

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