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Page:Popular Science Monthly Volume 90.djvu/368

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352

��Popular Science Monthly

��enlarging board.

Before each exposure, the size and position was obtained on the sketch of the whole picture. With the ruby or orange cover on the lens, the enlarging paper was placed exactly over the sketch paper. Then the exposure was made. Both papers were taken down before the next exposure, or changing of negative.

The effect of distance is obtained by making the object smaller and slightly undertiming the exposure. The longer the exposure,' the sharp- er, clearer, and nearer the object will appear to be when the paper is developed.

Exposure No. i was over a section of No. 7, and when the latter was made the former blocked out certain parts.

In exposures 8-9-10 the appearance of dis- tance was obtained by gaging the time of exposure and the size, and also, as in No. 8 and 10, by throwing the negatives slightly out of focus when exposing.

In exposure No. 1 1 , the cloud background was exposed over all the paper and greatly enlarged, only a section being used. Care as to the correct timing had to be taken. In fact the exposure was undertimed, as the least bit of overexposure would have spoiled the entire effect.

Care was taken^ at all times to avoid fog- ging of the enlarging paper.

A variety of beautiful as well as startling pictures can be made by this process of composite enlarging and printing. The average amateur as well as professional photographer has any number of negatives which when combined will make truly wonderful pictures — pictures that cannot be distinguished from actual photographs.

But patience is necessary. The "War in the Air" took four tries, and the last pic- ture consumed one hour and twenty minutes making the exposures.

���The photograph marked 9 is the same as Number 10 except that the latter is differently focused

���Hoisted by an Auto- mobile up to the Clouds

PERHAPS the queer- est use to which the automobile has been put is that illustrated in the photograph below. It shows a steeplejack rest- ing confidently on his nerve and on the end of a steel cable, the other end of which is attached to an automobile below. He is being hoisted to the top of a gigantic steel mast, towering high in the air, to give atten- tion to the antennas of the largest wireless plant in the United States, which is located at Bo- linas, California, about fifteen miles northwest of San Francisco.

A. A. Isbell, engineer in charge of the plant, states that the steeple- jacks prefer an auto- mobile to a horse for the hoisting, since the flat cattle range surrounding the base of the masts make the automobile practicable, and the ma- chine is more reliable and insures more steadi- ness in the ascent than a horse. The plant has nine of these great tubular steel masts, so that considerable work aloft is necessary.

���The other end of the cable is fastened to a moving automobile which is hoisting the jack three hundred feet to the top of the mast

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