the enterprise would prove a profitable investment.
As for the doctor, he rubbed his hands gleefully at the thought that before long the products of the United States would reach Australia on the very day of their manufacture, and vice versa. Surely this would be the grandest achievement science had yet witnessed!
The great, and in fact the only, difficulty toward putting the plan in operation was the boring of the hole. Imagine digging a well eight thousand miles deep! It was no easy task under any circumstances, and was rendered doubly difficult when the internal heat of the earth had to be taken into consideration.
But, perplexing as the problem was, Dr. Giles was the man to solve it, though it had required all his ingenuity to devise a machine that would do the work expeditiously and well. He had carefully prepared his plans and patterns beforehand; and as soon as the capital began to come in, he set about having the necessary machinery constructed.
The first question to be considered was, of course, the selection of a site for the tunnel. Dr. Giles, although living in Australia, was a native Ameri-
