Page:Popular Science Monthly Volume 90.djvu/661

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Popular Science Monthly

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���An Automatic Map-Maker. It Surveys by Wagon Jolts

THE photograph at the bottom of the page shows a map-making machine. It is the invention of Theodore Bodde, Westfield, N. J., and F. E. Austin, Hanover, , N. H. A shaft at the '■ forward end of the ma- chine is belted to a pulley attached to the hub of the rear wheel. This shaft is geared to a rod on which are mounted beveled wheels that rotate the map paper. One of the boards carries the drawing paper. A spring- supported pencil is arranged to mark on the paper as the wagon proceeds. When a map line has been drawn completely across the paper an alarm bell is automatically rung to warn the operator to shift the mechanism into position for making another map. So long as the machine or wagon is traveling on a level road both disks are stationary and only a straight map line is marked on the paper as it is moved 'past the pencil point. But when the wagon turns a corner, a set of g>-roscopes geared together are ar- ranged to turn the map board so that the map paper is also turned relatively to the pencil point, thus indicating the turn of the road by a deviation in the line marked on the paper. Any error in the marking that would naturally occur through an up-grade in the road is automatically corrected on the map by a pendulum at- tachment which regulates the rectilinear mo- tion of the map paper so that it is a 1 w a >' s in proportion to the horizontal length of the road. The ma- chine shown has been put to ac- tual use with entire success. The inventor claims that it is more reliable than the ordi- nary method.

����The wagon carries a revolving map paper and a spring- suspended pencil which records the lines of the road

��Scrape the bottoms of your shoes on the little iron bar and then wipe them on the mat before entering the automobile

��Don't Soil Your Car Floor— Wipe Your Feet at the Door

A SIMPLE but effective way of pre- venting muddy shoes from soiling the interior of an automobile has lately been brought out by William A. Roos, of New York city. It consists of a small square mat, with a short iron bar in front, which can be brought down flat on the running- board for use. The mat is made up of a number of short stiff bristles.

The bottoms of the shoes are scraped over the front iron bar, which projects over the edge of the running-board as shown, so the mud drops down to the ground. The dirt still remaining on the shoes can be removed by the bristles of the mat.

The device folds back into a pocket after it has been used. The last person entering the automobile catches the bottom of the bar with the toe of his shoe and swings it up. Catches on the hinges then hold the device close against the vertical side of the

running-board of the car.

The back of thematis enam- eled and finish- ed in such a way that it is not noticeable as a separate de- vice when fold- ed back into its pocket. The floor of the au- tomobile will thus be kept tidy and more comfortable in damp or sloppy weather.

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