inches. The prevailing colors of the ochres are red and yellow, but there occurs also in some parts a beautiful purple tinge, and in others a blackish-brown. At the Industrial Exhibition which took place in Montreal, in October 1850, some of the ochres of this locality presented to the public view by Mr. D. G. Labarre, attracted the attention of persons acquainted with the commercial value of such products, and arrangements were subsequently made with the proprietors of the land, by Messrs. H. A. Munroe & Co., of New York, for the purpose of entering upon such a preparation of the crude material as should fit it for sale. With this view, a couple of furnaces have been erected in the vicinity of the ochre bed, and an agent established to carry out the details of the manufacture, and attend to the forwarding of the article to New York, where the sale of it is effected. I was given to understand by the agent, that 400 barrels of the ochre had been disposed of at five dollars each, and that as many as twelve barrels had occasionally been prepared in a day. From the few natural colors that have been mentioned, eight tints are said to be prepared. The deposit being but little mixed with sand, the chief impurity to be got rid of consists of the roots of those plants which have been growing on the surface, some of which penetrate to a considerable depth. Two modes are resorted to for this purpose; one is by dry sifting, which is used where the natural colors of the ochres are to be preserved, as in the case of the yellow variety, of the purple, and of the blackish brown. The yellow is a hydrated peroxyd of iron, the purple also is probably in some peculiar state of hydration, but the red is the anhydrous peroxyd. By exposure to a sufficient heat in the furnace, the water of combination is driven off from the yellow and purple, and both becoming anhydrous peroxyd, assume the tint of the natural red ochre, from which, as from the other two, the vegetable matter in this operation is burnt out. The blackish-brown variety is scarcer than the others, and affords colors of a more valuable description; purified from roots without fire, it is sold under the name of raw sienna; it is admirably adapted for graining, and brings in retail, I am informed, so much as a shilling the pound. When subjected to fire, it assumes brown of less intensity, and it is sold as burnt sienna. As it does not turn red from burning, it is probable that there may be in this ochre, an admixture of manganese."

In the St. Malo range of the Seigneury of Cap-de-la-Madeleine a great deposit of ochre occurs. The area occupies upwards of

600 acres. It is underlaid by peat, the fuel sufficiently well adapted to prepare it for the market. This and many other locaties in Lower Canada, as well as in Upper Canada, contain inexhaustible quantities of ochre, some of excellent quality and of a great variety of colours.

STEATITE.

Steatite or soap stone, composed of flint and magnesia, possesses many singular properties which are gradually introducing the material into notice and use. It is generally soft to the touch, scarcely affected by acids, and little changed by exposure to intense heat.-In Maryland a steatite or soap-stone company exists, and manufactures a surprising number of articles for economical purposes. In addition to the properties before enumerated, the remarkable ease with which steatite is worked by common carpenters' tools, render it an object admirably adapted for may operations to which other materials are not applicable. A substance almost indestructible by fire and many strong acids, and so soft as to admit of being turned, bored, screwed together and planed, is well worthy of attention.

In Canada it is found and used as a refractory stone in the township of Vaudreuil, Beauce, Wotton and Ireland; it exists also in Sutton, Bolton and Melbourne; it also exists in the township of Leeds and Stanstead, where it is ground and employed as a paint.

The brief and necessarily imperfect sketch I have now given of the most important minerals hitherto found in Canadian rocks may serve to convey a tolerable impression of what our country offers to mining enterprise and industry. We must, however, in justice to that large extent of territory which constitutes our main mineral region, bear in mind that it is, in great part, still an uncultivated and but partially explored wilderness.

It was said by one, far above his fellowmen in acquirements, and in the additions he had made to human knowledge, that when at the close of a long life, he contemplated the work he had done, "he seemed like a child to have been gathering pebbles on the sea shore, with the vast ocean of truth lying unexplored before him." We may, with some semblance of propriety, apply this beautiful simile to our present acquaintance with the stores of inert wealth which lie hidden in the rocks of the unsettled parts of our country. Although the information which has been given to the world by the geological commission is of the highest national value, and in

amount, far greater than was ever expected to be acquired in so short a period, over a country so extensive and little known, and with means so inadequate to the end, yet it is not to be understood that discoveries equal in importance to those already made may not year by year inform us of fresh treasures before unthought of. It is only the other day that a band of rock was discovered, so admirably adapted to the milling purposes for which Burrstones are employed, that we may not only become independent of foreigners for that important article, but enabled to export them to other countries.

The discovery of hydraulic lime in some of the strata on which the city of Quebec stands tells, by means of a geological knowledge of the country, of the existence of hydraulic lime for hundreds of miles. The ascertained southern limits of the Huronian copper bearing rocks on lake Huron and Superior indicate a copper yielding country in which a search for that metal may be prosecuted over many thousand square miles with every prospect of suc

cess.

The influence indeed of a single discovery of an economic material in any strata acquires importance which cannot easily be estimated, when the known extent of the rock which holds it occupies wide areas. It is for this purpose that a general study of geological outlines of the country is so useful, and in our time even necessary. Think of the advantage to the settlers in the Ottawa region to know of the existence of Crystalline Limestones beneath their feet, over which they have been many years journeying 15 and 20 miles for the same indispensable material to the great River Ottawa itself, where it is exposed in a form to which they have been accustomed. But expand the ideas conveyed in this simple announcement to the whole region in Canada where it may apply, and we find that a knowledge of the structure of the Laurentian Rocks, which extend from Labrador to Lake Huron, and thence on towards the Mackenzie River, tells us of the existence of Crystalline Limestone throughout the whole of the vast country and limestone is an indispensable necessity of civilized life. But we may amplify still further and point to the iron ores generally associated with these limestones. I have spoken in a former lecture of the vast magnetic beds, of Marmora, Madoc, Belmont and Hull; these are generally found in juxta-position with beds of crystalline limestone. When this great fact becomes generally known among future settlers in the Laurentine Country, and they

are made aware of its applicability to the extensive areas between the Ottawa and Lake Huron and elsewhere, it becomes almost a matter of certainty that the large rivers traversing this region may thus be made accessible and of commercial value. Consider again the lime and soda felspar rocks which throughout the Laurentine Country are associated with the crystalline limestone, and remembering the words of Sir William Logan, we shall not despair of, but rather hope well for, this vast uninhabited region. The vallies underlaid by these lime and soda felspars guarantee a fertile soil and agricultural capability, wherever they are to be found, and the discovery of important ranges in the Laurentine Country establishes this capability over wide areas. It is of the highest importance to give due prominence to this part, for an impression has prevailed almost universally that the Laurentine Country, now comprising the unsurveyed part of Canada, is hopelessly sterile, and consequently incapable of supporting agricultural people so necessary in the proximity of a great mining district. Whereas the real facts of the case, when fully known, show conclusively that not only in the river vallies but over extensive ranges occupied by particular rocks, all the elements of fertility exist in singular abundance, and that it requires only the industrious hand of man to convert wide areas in those unoccupied solitudes into cultivated and fruitful farms.

ARTICLE IX.-Quarterly Journal of Microscopical Science. No. 18, January, 1857, p.p. 114, with six plates. London: John Churchill, 4s. CONTENTS.

Monograph of the Genus Abrothallus; by W. L. Lindsay, M. D., Perth. (An elaborate and erudite article of this obscure Genus of Lichens.)

The existence of Birds during the deposition of the Stones field Slate, proved by the comparison of the Microscopic Structure of certain bones in that formation with Recent Bones; by Rev. J. B. P. Dennis, F. G. S., Bury St. Edmunds.

On Dysteria; a new genus of Infusoria; by T. H. Huxley, F.R.S. On the Origin of Greensand and its Formation in the Oceans of the Present Epoch; by Prof. J. W. Bailey, N. Y.

Further Observations on Vegetable Growth; by the Hon. and Revd. S. G. Osborne.

On Striated Muscular Fibres in the Skin of the Human Lip; by Dr. Woodham Webb, London.

Translations, Notes and Correspondence, and Proceedings of the Microscopical Society.

This is an average number. From the notes we select the following communication addressed to the editors, which may prove interesting to microscopists among ourselves.

"Allow me to call your attention, and that of your readers, to a little contrivance of mine, which may be found useful."

"It is a simple apparatus for illuminating objects under the microscope, and will be found particularly of use when examining Diatomaceæ. Knowing that there are many microscopical observers like myself, not able to expend large sums in accessory apparatus to the microscope, I particularly recommend it to their notice."

It consists of a plate of glass, (fig. 1) (an ordinary slider,) three inches by one; to one side of which, in the centre, is attached, by

Canada balsam, a plano convex lens (L) and this may be of about one quarter-inch focus. Lenses of different powers can be used although I have found one of half-inch, and one of a quarter-inch focus to be the most useful. The way in which this is used is seen in the first figure. The rays of light (R) fall on the lens (L)