iron. The forged iron from this ore is commonly found to be hard, and very malleable, and has been used to furnish steel. It was formerly worked at the furnace known as Ridgely's furnace on the falls of the Great Gunpowder.

The whole amount of iron produced annually in the state of Maryland has been estimated at 5800 tons-valued at about $400,000; and it is thought that one half at least of this quantity is derived from the sources which have so far been enumerated.

From all these considerations, the undersigned are of opinion, that further researches into the mineral constitution of the portion of our state which they have so far passed in review, cannot fail to bring to light new sources of wealth, as well as to extend the operation of those that are already known; whilst they remain persuaded that where so many important interests are subserved, great and lasting benefits must accrue to the community at large.

The undersigned will now proceed to state the results of their observations on other parts of the state.

The second great division of Maryland, which may be made for the sake of convenience in its geological examination, will embrace that portion of territory lying between the line already defined, as limiting the upper part of the tertiary formation, and another drawn through the state from N. E. to S. W. passing along the summit of Parr's spring ridge, and coinciding nearly with the western limits of Baltimore, Anne Arundel, and Montgomery counties. This division will thus comprise the upper part of Cecil county, the greatest portion of Baltimore and Harford counties, the upper districts of Anne Arundel county, and the whole of Montgomery county. Its geological characters, are that it consists of stratified rocks, varying in mineral composition, alternating with each other, and sometimes passing one into another, in such a way as to render it very difficult to affix definite names to their different mixtures. When any of these rocks are viewed singly, they will rarely be found to present a simple mineral substance, constituting a large tract of country. They are, on the contrary, admixtures of several minerals and earths; the principal of which are, quartz, felspar, mica, hornblende, lime, magnesia, talc, &c. and according to the nature of their aggregation, and the predominance of one or the other, the rocks themselves are described in the systems by different names, as granite, gneiss, mica slate, hornblende rock, limestone, magnesian limestone, serpentine, steatite, (soapstone,) &c. These rocks are generally metalliferous, and, as a groupe, are usually called primitive or primary rocks.

If, first, we inquire into the nature of the soil by which these rocks are covered, it seems proper to base this inquiry upon the consideration that the soil (so far as its mineral constitution is concerned) is produced by the disintegration of the rock which immediately underlies it; whenever observed to be otherwise, it is presumed that it will always be found to have arisen, either from the circumstance of an encroachment of the tertiary formation upon the primary, or from partial transportations of soil from one spot to another by causes always appreciable. This view it is deemed important to take, as the only one calculated to lead to any general and positive results of value to agriculture. Thus every farmer in Baltimore county is aware of the higher estimate which is put upon the red soil of some districts, than upon the lighter colored soils of an adjoining one. Now, the red soil, as it is termed, is known to be produced by the decomposition of that variety of rocks, called hornblende rock; while the adjoining soil is derived from some other of the granitic aggregates. On the other hand, those portions of the same county that are designated as barren, are equally well known to occur principally among the magnesian and talcose rocks. Generally speaking, then, the mineral constituents of these soils will be found to correspond with those of the rocky strata beneath them. Although it is a remarkable fact in relation to the limestone soil, that its constituents do not indicate it to have been produced solely by the disintegration of the subjacent rock. Still however, the limestone soil, like the other soils that have been mentioned, is peculiar, and it is uniform, as regards superposition upon limestone rock; and as it shews no evidence of having been transported, must be classed among the primitive or original soils, whatever may have been the circumstances, hereafter to be discovered, that have occasioned its production.

If this view of the original constitution of the soils lying over the primary rocks be a correct one, and it is confidently believed to be so, it follows, that the first step to be taken by which to serve the agricultural interest of this portion of our state, is to discover and to establish the nature of each geological formation within it.

It is also a matter of interest to the farmer to know the limits of these formations. It interests him for example, to be made acquainted with the nearest spot from which he can derive his material for obtaining lime. Yet, even as regards the limestone formation, its limits have not been satisfactorily determined. From this circumstance, much inconvenience and disappointment have already arisen. Thus

the search after limestone is, at this time, anxiously kept up in many places, where it is possible, but barely possible, that it may be found; and it is also pursued in other localities, where it is not at all likely to occur. The aid of science is therefore required to hasten the fruition of any well founded hopes of this kind, as well as to remove the injurious tendency of fallacious expectations that ought no longer to be cherished. Already, but only within a short time, limestone has been found near Bell-air in Harford county. The excavations for the Baltimore and Ohio rail-road have exposed it in some parts of Baltimore county, where previously its existence was only suspected; and in some portions of Anne Arundel and Montgomery counties, on the Patuxent, the inhabitants have lately enjoyed the means, by its discovery in their neighborhood, of supplying themselves with a substance long earnestly desired, whose anticipated benefits they are now realizing. It is in this way, that by bringing to light new resources, new incentives to industry are created, the happy effects of which become in a short time apparent in the generally ameliorated condition of a large tract of surrounding country.

Before leaving this subject it may be stated, that the amount of lime, according to the inspections for the year 1832, which is annually brought to the city of Baltimore and applied to various purposes, is one hundred and sixty one thousand and one hundred bushels, to which, if there be added about an equal amount consumed in the country principally for the use of the soil, it may be made out, that this formation of limestone actually yields to the commercial and agricultural interests of Maryland, a yearly income of one hundred thousand dollars.

The other formations in this district would be found to yield, in proportion to their extent, perhaps larger returns. This is the case with the granite formations; whilst on the other hand, the soapstone formations, although not so extensively employed, are known to furnish a material of great value for the construction of hearths for furnaces and fire-places, for the making of stoves, &c.

The next step in the progress of inquiry, which the undersigned beg leave to recommend, would be, to indicate the localities of mineral deposites that are already known, or which in the course of examination might be discovered, to furnish materials for our manufactures. It would be necessary also to indicate the value of these materials in reference not only to their comparative qualities, but likewise to their precise nature. As an instance of the importance of VOL. XXVII.-No. 1.

3

the latter consideration it may be stated, that it has been found a matter of great moment to have ascertained the presence of a foreign metal in the rich iron ores of Deer creek, in Harford county. This ore, which contains from eighteen to twenty per cent. of the metal Titanium, and is hence called titaniferous iron ore, was found, in consequence of this admixture, to be exceedingly refractory. It cannot in fact, be smelted by itself; but requires to be mixed with some poorer ores before it can be made to yield its metal. Experiments directed by science have shown, that by mixing it, in the proportion of two parts to three, of an ore yielding thirty three per cent. of metal, it may be very readily worked. Similar considerations apply to those varieties of ore which, for the sake of distinction, might be called calciferous iron ores; and which for a long time were thought to require the addition of limestone, as a flux; these, likewise, experience has proved, not, however, until after considerable expenditure of time and money, to be perfectly manageable without it.

To be able to specify those different kinds of ore in the manner now indicated, it is evident that it will be frequently necessary to subject them to careful chemical analysis. The advantages, which those who have to use them will derive from such a specification, it is presumed, must be apparent. Nor do these considerations apply with less weight to the varieties of ores of iron which are not used for production of the metal. Among them, the chromiferous iron ores, which furnish a substance employed in a different branch of our manufacturing industry, require a separate mention. These, more usually called chrome ores, are known to be extensively employed for the production of several articles used as pigments and dyes. The value of the products annually obtained from this source is not less than fifty thousand dollars. The ore itself, too, is exported, and is understood to be in demand at the present time for the supply of foreign countries. The chief localities in Maryland are Harford county, Cooptown; Baltimore county, at the Bare hills, seven miles from the city of Baltimore, and at the Soldier's Delight, seventeen miles distant, and the northern part of Cecil county.

The serpentine formation, which encompasses the chromiferous iron ores, yields also another material for the preparation of a chemical product of great value. This is the epsom salt, the base of which is derived from a magnesian mineral, no where found in such abundance and purity as within the state of Maryland. The quantity produced

annually, is eleven hundred thousand pounds; valued at forty five thousand dollars; the exports are valued at forty thousand dollars. It is believed that the production of this article in Baltimore has entirely superseded the necessity of its importation for any portion of the United States, and has also greatly reduced its former price.

Still another substance, doubtless about to prove, ere long, a source of considerable revenue to the counties where it occurs, has been already alluded to as having been found in Cecil and Harford counties. It is the mineral commonly called porcelain clay or porcelain earth. This material is regarded as proceeding principally from the natural decomposition of the coarse-grained granite, a very common rock in the state of Maryland.

For the porcelain works at Philadelphia, it is derived, almost exclusively, from the neighborhood of Wilmington in Delaware; but an analogous formation was observed in Cecil county, eastward of the Big Elk, in the vicinity of the stopping place known as Dysart's. The mineral, called by mineralogists kaolin, is here well characterized, and is believed to occur in quantity; and as the undersigned know that demands for it have lately been made in Baltimore, they would indicate this locality as one likely to afford a supply. To the inhabitants of the county, it is well known as what is not unfrequently mistaken for limestone. Specimens of kaolin have been sent from Harford county also; but the exact locality has not been ascertained. The undersigned have likewise noted its occurrence on the route of the Baltimore and Ohio rail road, between Ellicott's Mills and Mariottsville.

Resuming now the consideration of the most prominent circumstances in the geology of that section of our state, which comprehends the primitive or primary rocks, and specifying the share of interest which belongs to each county within it; it will be seen that,

Cecil county possesses in her porcelain earth, an article of exchange likely to become soon of considerable value. The magnesian earths and chrome ores, abound towards her northwestern limits. The granite formation at Port Deposit is well known not to yield in value and importance to any in the state. To complete her advantages, and to supply proper materials for the industry of the agriculturists of the upper portion of the county, there seems to be wanting only a discovery of limestone, if not within her boundaries, at least at a more accessible distance than it is now known to exist.