The next day they arrived at the shore of Lake Ontario. Here they remained two days to make canoes out of the bark of the elm tree, in which they might travel to Niagara. For this purpose the Indians first cut down a tree, then stripped off the bark in one entire sheet of about eighteen feet in length, the incision being lengthwise. The canoe was now complete as to its bottom and sides. Its ends were next closed, by sewing the bark together; and a few ribs and bars being introduced, the architecture was finished. In this manner they made two canoes; of which one carried eight men, and the other nine.

A few days later Henry was handed over safe and sound to Sir William Johnson at Niagara. He was then given the command of a corps of Indian allies which was to accompany the expedition under General Bradstreet to raise the siege of Detroit, which important place had been long invested by a great Indian chief, Pontiac, who still carried on the war on behalf of King Louis XV. This enterprise was successful, and British control was extended to many places in central Canada. Henry returned to Fort Michili-Makinak and regained much of the property which he had lost in the Indian attacks. As some compensation for his former sufferings he received from the British commandant of Michili-Makinak the exclusive fur trade of Lake Superior.

The currency at that period, and long before, in Canadian history, was in beaver skins, which were approximately valued at the price of two shillings and sixpence a pound. Otter skins were valued at six shillings each, and marten skins at one shilling and sixpence, and others in proportion; but all these things were classed at being worth so many beaver skins or proportion of beaver skins. Thus, for example, the native canoemen and porters engaged by Henry for his winter hunts were paid each at the rate of a hundred pounds weight of beaver skins.[9]

At various places on the River Ontonagan, which flows into Lake Superior, Henry was shown the extraordinary deposits of copper, which presented itself to the eye in masses of various weight. The natives smelted the copper and beat it into spoons and bracelets. It was so absolutely pure of any alloy that it required nothing but to be beaten into shape. In one place Henry saw a mass of copper weighing not less than five tons, pure and malleable, so that with an axe he was able to cut off a portion weighing a hundred pounds. He conjectured that this huge mass of copper had at some time been dislodged from the side of a lofty hill and thence rolled into the position where he found it. Farther to the north of Lake Superior he found pieces of virgin copper remarkable for their form, some resembling leaves of vegetables, and others the shapes of animals.

In these journeys he collected some of the native traditions, amongst others that of the Great Hare, Naniboju, who was represented to him as the founder or creator of the Amerindian peoples. An island in Lake Superior was called Naniboju's burial place. Henry landed there, and "found on the projecting rocks a quantity of tobacco, rotting in the rain; together with kettles, broken guns, and a variety of other articles. His spirit is supposed to make this its constant residence; and here to preside over the lake, and over the Indians, in their navigation and fishing."

In the spring of the following year (1768), whilst the snow still lay many feet thick on the ground, he and his men made sugar from the maple trees on a mountain, and for nearly three weeks none of them ate anything but maple sugar, consuming a pound a day, desiring no other food, and waxing fat and strong on this diet. Then they returned to the banks of the Ontonagan River, where the wild fowl appeared in such abundance that one man, with a muzzle-loading gun, could kill in a day sufficient birds for the sustenance of fifty men. As soon as the ice and snow had melted, parties of Indians came in from their winter's hunt, bringing to Henry furs to pay him for all the goods he had advanced. In this way the whole of his outstanding credit was satisfied, with the exception of thirty skins, which represented the contribution due from one Indian who had died. In this case even, the man's family had sent all the skins they could gather together, and gradually acquitted themselves of the amount due, in order that the spirit of the dead man might rest in peace, which it could not do if his debts were not acquitted.

In the following autumn he had an experience which showed him how near famine was to great abundance, and how ready the Amerindians were in cases of even slight privation to turn cannibal, kill and eat the weaker members of the party. He was making an excursion to the Sault de Sainte Marie, and took with him three half-breed Canadians and a young Indian woman who was journeying in that direction to see her relations. As the distance was short, and they expected to obtain much fish by the way, they only took with them as provisions a quart of maize for each person. On the first night of their journey they encamped on the island of Naniboju and set their net to catch fish. But there arose a violent storm, which continued for three days, during which it was impossible for them to take up the net or to leave the island. In consequence of this they ate up all their maize. On the evening of the third day the storm abated, and they rushed to examine the net. It was gone! It was impossible to return to the point of their departure, where there would have been plenty of food, on account of the strong wind against them. They therefore steered for the Sault de Sainte Marie. But the wind veered round, and for nine days blew a strong gale against their progress in this direction, making the waves of the lake so high that they were obliged to take refuge on the shore.

Henry went out perpetually to hunt, but all he got during those nine days were two small snow-buntings. The Canadian half-breeds with him then calmly proposed to kill and feed upon the young woman. One of these men, indeed, admitted that he had had recourse to this expedient for sustaining life when wintering in the north-west and running out of food. But Henry indignantly repudiated the suggestion. Though very weak, he searched everywhere desperately for food, and at last found on a very high rock a thick lichen, called by the French Canadians tripe de roche,[10] looking, in fact, very much like slices of tripe. Henry fetched the men and the Indian woman, and they set to work gathering quantities of this lichen. The woman was well acquainted with the mode of preparing it, which was done by boiling it into a thick mucilage, looking rather like the white of an egg. On this they made hearty meals, though it had a bitter and disagreeable taste. After the ninth day of their sufferings the wind fell, they continued their journey, and met with kindly Indians, who supplied them with as many fish as they wanted. Nevertheless, they all were so ill afterwards that they nearly died, from the effects of the lichen diet.

Some time after this Henry resolved to search for the marvellous island of Yellow Sands,[11] an island of Lake Superior which, it is true, the French had discovered, but about which they kept up a good deal of mystery. The Indian legend was that the sands of this small island consisted of gold dust, and the Ojibwé Indians, having discovered this, and attempting to bring some away, they were disturbed by a supernatural being of amazing size, sixty feet in height, which strode into the water and commanded them to deliver back what they had taken away. Terrified at his gigantic stature, they complied with his request, since which time no Indian has ever dared to approach the haunted coast. Henry, however, with his men, finally discovered this Island of Yellow Sands in 1771, in the north-east part of Lake Superior. It was much smaller than he had been led to expect, and very low and studded with small lakes, probably made by the action of beavers damming up the little streams. He found no supernatural monster to dispute the island with him, but a number of large reindeer, so unused to the sight of man that they scarcely got out of his way, so that he was able to shoot as many as he wanted. The ancestors of these reindeer may have reached the island either by floating ice or by swimming. They seem, with the birds, to have been the island's only inhabitants, and to have increased and multiplied to a remarkable extent, small portions of the island's surface being actually formed of immense accumulations of reindeer bones.

Amongst the birds of the island, besides geese and pigeons, were hawks. No serpents whatever were seen by the party, but Henry remarks that the hawks nearly made up for them in abundance and ferocity. They appeared very angry at the intrusion of these strangers on the sacred island, and hovered round perpetually, swooping at their faces and even carrying off their caps.