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A Flying Scale Model Aeroplane

A Flying Scale Model Aeroplane The little aeroplane has been specially designed for this activity for easy construction and cheapness, and is a 3/8 inch to the foot scale model of the D.H. Moth Minor. The original model has been properly tried out and has won admiration for its pretty flying. Its looks can be judged from the photograhs, Fig …

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Camera Stereoscopic Slides

Camera Stereoscopic Slides Have you ever looked through a stereoscope at a pair of pictures and noted how marvelously everything stands out in relief? As you probably know, two picture almost identically alike are needed in order to provide the stereoscopic effect. When the pictures are made by photography, two exposures are necessary, one taken with the lens in the …

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They Change Places

They Change Places This experiment is rather difficult to perform because its success depends on exact conditions; it is, nevertheless, well worth all the trouble you may expend on getting it accurate. Look first at the accompanying drawing. You will see two wine glasses, one inverted over the other. Naturally, this will call for two glasses of exactly similar dimensions. …

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