within the areas traversed by these streams. Our course, in passing up and down, was obstructed by beaver-dams at short intervals, from two to three feet high, over which we were compelled to draw our boat. Their numbers and magnitude could not fail to surprise as well as interest any observer. Although constructed in the solitude of the wilderness, where the forces of Nature were still actively at work, it was evident that they had existed and been maintained for centuries by the permanent impression produced upon the rugged features of the country. The results of the persevering labors of the beaver were suggestive of human industry. The streams were bordered continuously with beaver meadows, formed by overflows by means of these dams, which had destroyed the timber upon the adjacent lands. Fallen trees, excavated canals, lodges, and burrows, filled up the measure of their works. These together seemed to me to afford a much greater promise of pleasure than could be gained with the fish-pole, and very soon, accordingly, the beaver was substituted for the trout. I took up the subject, as I did fishing, for summer recreation. In the year 1861 I had occasion to visit the Ked River settlement in the Hudson's Bay Territory, and in 1862 to ascend the Missouri River to the Rocky Mountains, which enabled me to compare the works of the beaver in these localities with those on Lake Superior. At the outset I had no expectation of following up the subject year after year, but was led on by the interest which it awakened, until the materials collected seemed to be worth arranging for publication. "Whether this last surmise is well or ill founded, I am at least certain that no other animal will be allowed to entrap the unambitious author so completely as he confesses himself to have been by the beaver. My unrestrained curiosity has cost me a good deal of time and labor.

When the romantic features of the discovery and conquest of Mexico, which made such a powerful impression upon the writers of the sixteenth and seventeenth centuries, and which have not yet lost their influence, shall become softened down by our increasing knowledge of Indian character, arts, and institutions, it will be possible to reconstruct, from existing materials, a rational history of this interesting people. If the author of the volume, whoever he may be, will entitle his work 'A History of the Aztec Confederacy,' and, after explaining the political relations of the three nations of which it was composed, and the functions of the council by which it was governed, will then introduce Montezuma