The most tempting solution of this question of washing seems to be found in the use of large pools of running tepid water; but such a process is too costly for general use, and the most economical one, without doubt, consists in giving tepid douches.

[Illustration:  TEPID WATER DOUCHE]

To our knowledge, the only apparatus in this line that has been devised was exhibited last year at the exhibition of hygiene in the Loban barracks.  It has been used daily for six years in several garrisons, and therefore has the sanction of practice.

This apparatus, which is due to Mr. Herbet, consists of a steam boiler and of an ejector fixed to a reservoir of water and provided with a rubber tube to which a nozzle is attached.  The steam generated in the boiler passes into the ejector, sucks up the water and forces it out in a tepid state.

The apparatus thus established did not sufficiently fulfill the purpose for which it was designed.  It was necessary to have a means of varying the temperature of the water projected, according to the season and temperature of the air, to have an instantaneous and simple method of regulating the apparatus, that could be understood by any operator, and to have the apparatus under the control of the person holding the nozzle.  These difficulties have been solved very simply by causing the orifice of the nozzle to vary.  This nozzle, from whence the jet escapes, is formed of rings that screw together.  When the nozzle is entire, the jet escapes at a temperature of say 40 deg..  When the first ring is unscrewed, the water will make its exit at a temperature of 38 deg..  In order to lower the temperature still further, it is only necessary to unscrew the other rings in succession, until the desired temperature has been obtained.

As it is, the apparatus is rendering great services where it has been introduced; for example, at Besancon and Belfort.  It serves, in fact, for an entire garrison, while that before, the washing was done in each regiment, thus requiring the use of much space and causing much loss of time.

Eight men are washed at once for five minutes, say 96 men per hour.  Every minute the men turn right about face, and when they are in file each rubs the other’s back.

Twenty-two pounds of coal and 260 gallons of water are consumed per hour, and the boiler produces 130 lb. of steam.—­Le Genie Civil.

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HOW TO MAKE A STAR FINDER.

Being all of wood, it is easily made by any one who can use a few tools, the only bit of lathe work necessary being the turned shoulder, K, of polar axis.  A is the baseboard, 9 in. by 5 in., near each corner of which is inserted an ordinary wood screw, S S, for the purpose of leveling the base, to which two side pieces are nailed, having the angle, x, equal to the co-latitude of the place.  On to these