implements with it, just as the loose ballast in the hold of a vessel is shifted and rolled from one side to another.

No one who attentively examines these implements can doubt hat they are the products of human skill. Rude and uncouthas they may appear, that rudeness is probably not so much due to any deficiency of intelligence in the manufacturer as to the want of iron or some other metals wherewith to work. Probably no workman who found himself destitute of metal would be able to produce from flint-pebbles more useful or elegant implements. Those who are familiar with the forms which are presented in those flints which are casually fractured, will agree that it is almost impossible that even a single flint should be so fractured by accident as to assume the shape of these implements; but here we have a great number, all taken from a single quarry. Further, it will be seen that the original or natural surface is never retained where t at all interferes with the shape and symmetry of the weapon. Whenever it would have so interfered, chiefly on the sides and at the point, it has been chipped away; and thus there has been no waste of labour, nothing having been removed but that which was inconvenient. It will also be noticed that they are all formed after a certain rude but uniform pattern; they are worked to a blunt point, at one end, with a rude cutting edge on each side, and a sort of boss at the other extremity, forming a handle or hand-hold. In order the better to form this double edge, a ridge s left running down the centre; and the edges have been formed by striking away the flint in splinters from each side, in a direction at right angles with, or a little oblique to, the axis, the base or under side being usually either flat, or but slightly con

vex.

The discovery of these implements under the circumstances indicated cannot fail to suggest many interesting inquiries. We should all desire to know something more concerning the persons by whom, and the purposes for which, they were fabricated,-how it happened that so many of them were brought together in so small a space,and how it is that no remains have hitherto been found of those by whom they were made and used. These, however are speculations which seem to belong to the province of archaology rather than to that of geology; and they are only now alluded to by way of suggestion that topics of such importance and interest are well deserving of the investigation of archeologists."Quarterly Journal of the Geological Society.

By

ARTICLE VI.-On some points in American Geology.
T. STERRY HUNT, F.R.S., of the Geological Survey of Canada.

(From the American Journal of Science No. 93, 1861.) The recent publication of two important volumes on American geology seems to afford a fitting occasion for reviewing some questions connected with the progress of geological science, and with the history of the older rock formations of North America. The first of these works is the third volume of the Paleontology of New York by James Hall; we shall not attempt the task of noticing the continuation of this author's labors in the study of organic remains, labors which have by common consent placed him at the head of American paleontologists, but we have to call attention to the introduction to this 3rd volume, where in about a hundred pages Mr. Hall gives us a clear and admirable summary of the principal facts in the geology of the United States and Canada, followed by some theoretical notions on the formation of mountain chains, metamorphism and volcanic phenomena, where these questions are discussed from a point of view which we conceive to be of the greatest importance for the future of geological science. A publication of this introduction in a separate form, with some additions, would we think be most acceptable to the scientific public.

CAN. NAT.

1

VOL. VI. No. 2.

The other work before us is Prof. H. D. Rogers' elaborate report on the geology of Pennsylvania, giving the results of the Survey of that State for many years carried on under his direction, and embracing a minute description of those grand exhibitions of structural geology, which have rendered that State classic ground for the student. The volumes are copiously illustrated with maps, sections and figures of organic remains, and the admirable studies on the coal fields of Pennsylvania and Great Britain add much to its value.

The oldest series of rocks known in America is that which has been investigated by the officers of the Geological Survey of Canada, and by them designated the Laurentian system. It is now several years since we suggested that these rocks are the equivalents of the oldest crystalline strata of western Scotland and Scandinavia. This identity has since been established by Sir R. I. Murchison in his late remarkable researches in the north-western Highlands, and he has adopted the name of the Laurentian system for these ancient rocks of Ross, Sutherland, and the Western Islands, which he at first called fundamental gneiss. These are undoubtedly the oldest known strata of the earth's crust, and therefore offer peculiar interest to the geologist. As displayed in the Laurentide and Adirondack mountains, they exhibit a volume which has been estimated by Sir William Logan to be equal to the whole paleozoic series of North America in its greatest development. The Laurentian series consists of gneiss, generally granitoid, with great beds of quartzite, sometimes conglomerate, and three or more limestone formations, (one 1000 feet in thickness) associated with dolomites, serpentines, plumbago, and iron ores. In the upper portion of the series an extensive formation of rocks, consisting chiefly of basic feldspars without quartz and with more or less pyroxene, is met with. The peculiar characters of these latter strata, not less than the absence of argillites and talcose and chloritic schists, conjoined with various other mineralogical characteristics seem to distinguish the Laurentian series throughout its whole extent, so far as yet studied, from any other system of crystalline strata. It appears not improbable that future researches will enable us to divide this series of rocks into two or more distinct systems.

Esquisse Géologique du Canada, 1855, p. 17.

† Quar. Journal Geol. Society, vol. xv, 353; xv. ; 215.