Page:Popular Science Monthly Volume 72.djvu/71

 with but few other substances that man produces. If you are a farmer, and produce wheat, cotton, tobacco or any other of the ordinary farm products, you know very well by experience that when the harvest season comes around again the crop that you sold last year will practically have disappeared, and there will be room in the markets for the new one you have for sale. Your wheat will have been eaten up, your cotton woven into clothing and your tobacco disposed of in the form of smoke. If you are a producer of food animals, or a fisherman, the same will have happened. If you are a lumberman your boards will have been put into buildings or furniture, which in due time must be renewed. If you are a coal miner your crop is transformed by the consumer into gas and smoke about as fast as you dig it from the earth. If you are an iron, copper, lead or zinc miner your commodity begins to deteriorate in value the instant it goes into usage, and in five, ten, twenty or fifty years at the utmost the articles into which the bulk of these metals are worked up will have rusted or worn out and must be replaced.

But not so with gold. The coin you hold in your hand to-day may, for all you know, have been part of the gilding of the dome of King Solomon's temple, in Jerusalem. The case of the watch in your pocket was perhaps taken from the mines of Spain by the early Romans, a thousand years before our era. The ring you give your betrothed may be wrought from a lump of metal washed by the prehistoric miner from the stream beds of Rhodesia or India.

Who can tell? For gold can not be eaten or burned up. It can only be lost, and the whole world is interested in preventing that fate, and in taking the greatest of precautions against its diminution by wear. Hence gold is what may be called a cumulative crop. The quantity in the hands of man would continually increase, if the crop were a regular one and loss could be prevented. To a certain extent the same is true of silver, but there are no other manufactured substances, except these two metals and the gem stones, that do not steadily and even rapidly deteriorate or disappear. Even gold is somewhat subject to the law of decay, for that part of the annual crop that is used in dentistry, in photography and in gilding is rarely employed again for any other purpose, and in a generation or two has gone back to earth.

How then about the annual crop of gold? Whence does it come, what does it amount to, and how long can we go on extracting it from the bowels of the earth without disturbing the qualities that it seems to have in the commercial and industrial world? These are interesting questions that can only be answered by looking backward into the history of the metal, as well as considering its position at the present day.