Page:Popular Science Monthly Volume 89.djvu/476

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��Popular Science Monthly

��An Improved Vacuum Bottle

ANEW type of vacuum l)ottlc made entirely of steel with a pure white porcelain enamel lining — will shortly be placed upon the market. The steel bottle is the in\ention of Mr. William Stanley, who perfected the bottle while engaged with other scientists, notably Dr. Ir\ing Langmuir, in studying heat insulation.

This new bottle is non-breakable and the inventor claims about ten per cent, more efficiency for it ihan the glass bot- tles heretofore in use. It overcomes the well-known scientific fact that all metals ha\'c buried within them and condensed on their surface varying amounts of gases, which in their total amount to sur- prising quantities, being many times the actual volume of the metal. When a high vacuum is produced adjacent to a metal surface these gases free themselves slowly and for a long time continue to appear in the vacuous space.

The inventor believes that this phe- nomenon of occluded gas was responsible for the failure to obtain in metal-wall vessels results obtained in glass vacuum- bottles. He, therefore, obtained the de- sired result, not by spacing the inner and outer wall extremely close together, but by filling the vacuous space between the walls witii a very fuiely divided metal so prepared as to be incapable of giving off gas at a vacuum or even to be absorptive of gas in the vacuum. By this procedure each air space enclosed between the granules of the finely fitted material Ijecomes a vacuous space of which the granules form the vacuum walls.

The bottle is made by electrical welding which makes the joints not only vacuum light but stronger than the sheet metal itself. Although built up of a number of parts this container is one .solid metal unit when coiupleted. The method of construct ion eliminates all danger of break- ing at the joints. In fact the bottle is claimed to be prac- tically indestructible under even the most strenuous usage short of smashing with an axe with malicious inlciit.

���Vacuous Space Filled with Finely Divided

Metal

��Facilitates Boiling Water

THIS novel idea of a tube-kettle will be found to give very satisfactory results where water is re(|uired to be boiled in one-third to half the usual time.

The sketch shows an ordi- nary kettle so fitted, five holes being bored to correspond, both top and bottom.

In these holes tubes of half-inch to one inch bore are fitted, the bore varying according to the kettle's size, after which they are well soldered to prevent leakage. Kettles fitted with these tubes are suitable for use on either gas stoves or a closed range, and are also rendered suit- able for open grates by fitting corks in the top of the tubes to prevent any smok- ing.

Practically all kinds of kettles may be readily converted into tube-kettles in this way. — George M. Holden.

Using Waterproof Lutes TDOILED linseed oil, thickened

��with lead, Care

���Water May Be Boiled

in One Third of the

Usual Time

��X3 clay, asbestos, or red or white

forms a good waterproof lute.

should be taken to make it thick enough. Flaxseed meal made into a stiff paste

with water is useful for steam con- nections and is easily ap- plied.

I'ortland cement is water- proof onK' when gi\-en time for preliminary setting to take place. It is not generally impervious to water, and be- cause of its colloidal character while setting, it seems incred- ible that it could ever act other than as a water-pervious diaphragm. When firmly set antl dry, however, the colloid character is lost. For practi- cal (iur[)oses, jireparationscon- taining metallic soaps or oil enmlsions serve to render con- crete approximately imper- \ious to water.

��HEAVILY NICKELED CUP— LARGE 5CE SANITARY NECK POURING SURFACE PORCELAIN

COVERED HEAVILY NICKEtLD

THREAD PItCt RUGCEO STftL OUTSIDC WELL

��PURE WHITE

PORCELAIN

ENAMEL LININi STEEL. IN5IDI ■SMELL

STEEU SurPOKTS METALLIC tXHAUSnON TUBE -HEAI^ 5IEEL

Bonon

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