RUBBER.—The use of rubber has grown wonderfully in the last ten years. Every year a rubber famine is predicted, and every year someone announces that a substitute has been found that is just as good as the real article. The facts seems to indicate that neither the famine nor the substitute is really at hand. Rubber plantations are being extended in Mexico to meet the demands of the growing trade, but the bulk of our rubber still comes from the Amazon country in South America, and that country is almost limitless in its supplies of this article. It is true that the trees along the banks of the rivers have been tapped until their product is much inferior to what it once was, but this condition exists only for a distance of two or three miles along the river banks. There are plenty of magnificent trees standing untouched a little farther back. All that is needed to get more rubber is to get more men into these forests gathering it. The real difficulty is to get the men to do the work. The finest rubber forests remaining near the river fronts are along the Purus, one of the large rivers flowing into the Amazon from the south.
SUNSHINE CAUGHT.—For thousands of years men have tried to use the heat of the sun's rays in the place of fire. It is now claimed that Dr. William Calver of Washington has finished an invention which will bring into the space of a few inches all the rays of heat from the sun that would naturally fall upon one acre of ground. By bringing so many rays to a focus he gets such a powerful heat that iron and steel melt in it like icicles.
A magnifying glass or lens of almost any sort held in the sunshine makes a bright, warm spot. Dr. Calver's machine gets the same effect, only more powerfully. He has secured a temperature of several thousand degrees Fahrenheit. To make his machine useful for heating houses and making steam for factories he has invented a reservoir to store the heat gathered while the sun is shining, so that it may be used at night or on dark days. Men of science have been looking for such a machine for a long time, and if Dr. Calver and his friends are not much mistaken his invention will be as great a help to civilization as the harnessing of Niagara Falls for electric work. His laboratory is in the outskirts of Washington, D. C.
WASHINGTON'S MONUMENT.
GEO. P. MORRIS.
A monument to Washington?
A tablet graven with his name?
Green be the mound it stands upon,
And everlasting as his fame!