Page:Popular Science Monthly Volume 92.djvu/522

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��Popular Science Monffih/

���the range. As the cloud of smoke bursts in the air, it represents within certain limits the entrenched position of the enemy. As he sees the smoke curl upward, the commanding officer gives his directions to the gunners. The gun crews im- mediately answer with dummy rounds of ammunition. As the bombs go off in different quart- ers and at different heights, they see to it that the guns are trained to bear on the point where the enemy fire originates, and not on the actual pJace where the cloud of smoke is observed. In this way they get accurate training, and more complete preparation for actual service "over there."

��A^

��No, they're not fumigating an orchard. The puff of smoke is a target for artillery practise

Our Artillery Shoots at Curling Smoke for Practice

SOMEWHERE in the United States" our artillerymen are practising. They have to have something to shoot at. Recently ingenious soldiers rigged up the apparatus shown in the accompanying illustration. It consists of a long pole at the end of which is a container for holding two ounces of black powder. This is ignited by pulling a string. A per- cussion cap is sot off. The resulting puff of smoke sim- ulates a bursting shrapnel closely. Somewhere in the distance are a line of artillerymen, who want to get

���Here is operated

��an by

��It's Beginning to Rain, So Bang! Goes the Windov,'

N automatic device which

takes care of the windows

of a house or apartment, and

closes them when it begins to

rain, has been perfected by

L. M. Phelps of Philadelphia.

It is quite automatic and its

action is said to be positive.

In his device a loop lever, connected with

a stationary rod attached as a permanent

fixture to the lower corner of the upper

window sash, is held in position by a

narrow strip of blotting paper. So long

as the paper is dry it is rigid enough to

hold the delicately adjusted lever, but a

single drop of rain will so soften the paper

that it allows the loop of the lever to fall

and thus to release the pressure of the

lever against the

lower sash. Since

the sash is weighted

with a bag of sand

or small shot, it

will drop and close

t he window against

the rain.

In addition to acting in case of rain it can be made to work at a pre- determined time by alarm-clock.

��autonijitic window-closer a strip of blotting paper

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