CHEMICAL INDUSTRIES AND THE RAW MATERIALS IN MARYLAND*
The mineral resources of Maryland are summarized and the influence of their occurrence in the state on the location of the early chemical industries i n the United States i s indicated.
. . . . . . The chemical industries in Maryland now have little connection with the natural resources or mineral deposits of the state though their location in Maryland, particularly in the vicinity of Baltimore, is largely due to the low-grade deposits which could he utilized to advantage in the early days of the Province before the richer deposits in various parts of the United States were discovered. In general the mineral resources of the state conform to the long recognized three-fold division of the physiography and geological formations, viz., the Coastal Plain, the Piedmont Plateau, and the Appalachian Region. In the coastal plain portion of the state which includes all that part of the state lying southeast of the Baltimore and Ohio and Pennsylvania railroads running from Wilmington to Washington, the deposits consist of clays, sands, and gravels which form the raw materials for the extensive ceramic establishments centered about Baltimore. The quality of these clays is that of those found along the greater part of the eastern coast of the United States from New England southward and has been the basis of common brick and terra cotta manufacture, with occasional plants for the better grade of porcelain ware. In the coastal plain deposits is also found the diatomaceous earth, which is composed of the microscopic hard parts of diatoms, which have been worked from time to time in the manufacture of absorbents and heat-retaining coverings. Its use as a Fuller's earth has never been successfully developed as the low refractoriness of these gelatinous micro-organisms has prevented the development of any manufacture of refractory ware. In the Piedmont area, which extends westward from the coastal plain to the Blue Ridge, are a series of highly crystalline ancient rocks composed of old sediments and great masses of intrusive granites and gabbros with occasional lava flows from volcanoes active before the time of organic life in this region. It is in this area that all of the chrome, copper, magnesia, and a large part of the iron occur which has occasioned localization of *Editor's Note: This paper was written at the request of the editor as part of a survey of the chemical industries, resources, and education of Maryland. For various reasons it has seemed advisable to abandon the idea of compiling individual state surveys. Nevertheless, it is felt that this paper will be of interest to many of our readers; hence it is presented herewith. t State Geologist. 485
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chemical industries in Baltimore. Probably the most interesting products, from the chemical standpoint, are associated with the small areas of serpentine such as are found a t the Bare Hills. Soldier's Delight, and in a line across Harford County to the Pennsylvania line in northern Cecil County. It was in these serpentines that the chrome and magnesium carbonate were found which were the occasion for the development of the Baltimore Chrome Works and some of the pharmaceutical laboratories in Baltimore city. About a century ago Dr. H. H. Hayden recognized that some of the white veins in the serpentine were composed of the magnesium carbonate and from this material there began a small manufacture of Epsom salt for medicinal purposes. These veinlets were never very large or particularly pure but served to start the manufacture of pharmaceutical compounds which are now entirely derived from raw materials brought into Baltimore from all parts of the world. The discovery of the value and utilization of the black component of the serpentine, known as chromite, is an interesting illustration of the keen observation and utilization of a young man who applied his casually acquired knowledge a t the opportune moment. According to the story, Philip Tyson, who had traveled abroad and had visited chrome works in Glasgow, noticed that the hogsheads brought into the Baltimore market by a farmer were held in place by black rocks which appeared similar to the raw material used in the manufacture of chromium salts in Glasgow. Young Tyson sought out the source of these black masses and found that they had come from the serpentine areas above mentioned. He examined the ground, found the deposits as well as many others of similar character in the serpentine barrens of the state, secured title to these apparently worthless lands, and undertook the manufacture of chromium salts from this material. From this small beginning was developed a large family fortune and the establishment of the Baltimore Chrome Works where, it is interesting to note, the first industrial chemist was employed. It was not long before richer deposits of chromite were found in other parts of the world which have been the source of most of the raw material refined in the Baltimore Chrome Works and it was soon realized that the lean deposits found in Maryland could not be worked profitably in competition with the richer deposits found in the Far East. Attempts have been made from time to time to operate these local deposits of chromite but never with success except under peculiar conditions. Even during the recent war when the receipt of chromite was shut off and the price rose to an abnormal figure, i t was found practically impossible to secure an appreciable amount of the raw material a t a profit. Occasional washings of chrome sands in a small way by individuals are, however, still camed on in Cecil County and probably also in the Baltimore County serpentine area.
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In the same area of the Piedmont are found the few copper deposits of the state which in the old days were found to be sufficiently rich to warrant exploitation and to furnish a source of some of the material which was refined in the Baltimore Copper Works. I t has been frequently stated that the copper deposits of the Bare Hills north of Baltimore, in the vicinity of Sykesville, and in Frederick County, were the occasion for the establishment of the Baltimore Copper Works but it seems more probable that this establishment relied upon raw materials from South America and later from the western states. Prior to the establishment of the Baltimore Copper Works, copper was refined and rolled in a small way in connection with the iron furnaces, the copper coming from outside the state. When the much purer and richer deposits of copper were found in the Lake Superior region and later in the well-known copper camps of the far west we realized that the lean, hard ores of the Maryland occurrences could not be worked profitably. Attempts have been made from time to time to open the old mines a t Liberty or at New London and also at Bare Hills hut the conditions are not favorable for successful development of the copper industry based upon these raw materials. Now most of the old workings are marked only by dumps which serve as a hunting ground for mineral collectors. The manufacture of iron in Maryland was once an active industry with furnaces, forges, and rolling mills a t many points along the southern edge of the Piedmont where the carbonate ores of the coastal plain could be worked by means of the water power of the Piedmont. The fact that it was possible to secure the raw materials for iron in Maryland was early recognized and the industry of exporting iron to England had come into being by 1718. About this time Washington's father and halfbrother became interested in the industry and their company soon outranked all others in America in the manufacture of pig and bar iron. While most of the earlier furnaces were near tidewater, the manufacture of iron had commenced in Frederick County prior to the Revolution but the works in the neighborhood of Cumberland were not developed until a century later. The substitution of steel for the higher grades of iron in many forms, the discovery of extensive deposits of rich ores in other sections of our country, particularly in Michigan, Minnesota, and the southern states, coupled with the wonderful extension and cheapening of transportation, have resulted, within the past few years, in such improvements in the methods of producing iron and steel and in cheapening their cost, as have driven out the charcoal furnace and hloomery, and, under the principle of the survival of the fittest have left no place for the lean ores of Maryland and the antiquated methods of other days.
The present era of iron manufacture in Maryland with the extensive works along the shores of the Baltimore harbor is based upon a new prin-
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ciple, viz., the location of plants on the seaboard where the rich ores from foreign lands may be brought to he worked by coal from the nearby coal fields. In the perfection of sites for this combination Sparrows Point is unsurpassed. Raw ores from all parts of the world may be delivered directly to its works while coal may be secured under competitive conditions by rail or water delivery and the distribution of its finished product has a similar transportation advantage. The daily production of a single modern steel plant may easily exceed the total annual production of the many forges and furnaces of the early days. The manufacture of cement represents a chemical industry based upon raw materials drawn from the Piedmont area and from the Appalachians to the westward. Originally limestones were selected of a composition which approximated that of portland cement and the so-called natural cement works a t Cumherland and Haucock, where they secured desirable rock from nearby ledges, long maintained an enviable reputation. At the present time the larger cement works, like those a t Hagerstown and Union Bridge, do not trust to varying composition of the natural rock but produce their products by the careful mixture of the various ingredients selected from scattered points, the variations of chemical composition being controlled by numerous analyses. The modern cement plants are expensive and the operators cannot afford to produce other than uniform high-grade products of cement and hydrated lime. Materials of less importance found in the Piedmont area which enter into the chemical industries include quartz and feldspar. These minerals occur in the form of pegmatite dikes which are so coarse-grained that the individual minerals may he separated by hand cohbing into a form ready for use in the ceramic industry. A little of the material is used in the state but most of it is sent either to the large pottery works of New Jersey or to East Liverpool, Ohio. Pegmatite dikes of this character are found widely scattered in the crystalline rocks of the world and become of economic importance only when it is possible to secure the individual constituents in great purity. They occur most abundantly in the valley of the Patapsco River and a t various points in Harford and Cecil counties. Some of them carry the potassium feldspar orthoclase; others the sodium feldspar albite. The ratio of the feldspar to the quartz is not constant but tends to approach the eutectic mixture of seventy-two per cent feldspar and twenty-eight per cent quartz. When the grain becomes too small to separate the quartz from the feldspar and particularly the small flakes of mica and other constituents carrying iron which would color the porcelain ware, these deposits become worthless. In the western part of the state beyond Cumberland are the great deposits of high-grade coal which occur in a series of strata, some of them like the "Big Vein" of unusual size and purity. Because of their quality
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they are not used directly in the chemical industries but become a chief source of power. The coal area of Maryland has an extent of approximately four hundred fifty-fivesquare milesand the original supply, before erosion or mining, has beeu estimated as over eight billion tons. The annual production is about four million tons and the total exhaustion something over eight million tons, leaving the greater portion of the original supply still in the ground. Beneath the coal occurs a stratum of highly refractory fire clay which has beeu the basis of an extensive industry in the manufacture of enameled brick. The high-grade fire clay is used for the manufacture of the highclass brick, and on it is flowed an enamel mixture of fire clay and fusible constituents which may be melted into glass without fusion of the brick itself. The compounding of a glaze which will have shrinkage value the same as that of the underlying brick during cooling is one of the most delicate chemical processes camed on among the chemical industries in Maryland. The foregoing discussion of the chemical industries of the state shows that while the raw materials of Maryland a t the present time are but little used, their occurrence in the state during the period of infancy of the chemical industries in the United States exercised a powerful influence in determining the location of these chemical works. It is also interesting to recall that i t was the chrome industry in Maryland which led to the first regular employment of a chemical engineer in the United States.