Being possessed of much more than the average amount of ability and enthusiasm, he was chosen by Moses Norton, the energetic Governor of Fort Prince of Wales, to go out with the Indians into the vast, and as far as that was then known, limitless, territory west of Hudson Bay, in order to find and prospect the place where the native copper had been found which the Indians often brought with them to the fort.

During the year preceding his departure on his first expedition, he had had an excellent opportunity to perfect himself in a knowledge of astronomical and geodetic work, for in the summer of 1768 the annual ship had brought William Wales, F.R.S., and Joseph Dymond from London, commissioned by the Royal Society to remain at Fort Prince of Wales throughout the ensuing year in order to observe the transit of Venus over the sun on the 3rd of June 1769.[2] They remained at the fort until the ship left again for London in August of the following year (1769). Mr. Wales was one of the foremost astronomers, mathematicians, and litterateurs of his age. Shortly after his return to England he was appointed to accompany Captain Cook on his voyage around the world in the Resolution in 1772-74, and again on his last voyage in 1776-79. His presence for more than a year among the little band of white men assembled at this remote fur-trading post on Hudson Bay must have had a helpful influence in preparing Hearne for his great explorations overland to the Arctic Ocean. This book is an account of three journeys which he undertook in rapid succession into the country west of Hudson Bay and north-west of Fort Prince of Wales in search of the fabled bed of copper ore, from which pure copper could be loaded directly into ships at trifling expense. In the first and second journeys he was obliged to turn back before reaching his destination, but in the third journey all difficulties were finally overcome, and he was taken to and shown the "mine" of copper.

It has been my good fortune to travel over parts of the same country through which Hearne had journeyed one hundred and twenty-three years before me, and into which no white man had ventured during the intervening time. The conditions which I found were just such as he describes, except that the inhabitants had changed. The Chipewyan Indians, whom he found occupying advantageous positions everywhere as far as the north end of Dubawnt Lake, had disappeared, and in their places the country had been occupied by scattered bands and families of Eskimos, who had almost forgotten the ocean shores of the north, from which they had come. They were depending entirely, for food and clothing, on the caribou, which they killed on the banks of the inland streams and lakes. Traces of old Indian encampments were seen in a few of the scattered groves that are growing along the banks of Dubawnt and Kazan Rivers, but these camps had evidently not been occupied for many years.[3]