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Page:Popular Science Monthly Volume 17.djvu/827

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THE INDIA-RUBBER INDUSTRIES.
807

of unvulcanized India-rubber. Here is a strip of India-rubber; you see that it is quite soft and pliable. I will now expose it for a few minutes to a temperature of 0° Centigrade, or the freezing-point of

Fig. 2.—The Operation of drying the India-rubber Juice.

water. It becomes, as you see, rigid and stiff, but its original pliability may be restored, either by warming, or by applying sufficient tensile strain to it, to extend it to three or four times its length. One half