The place on which the Silver mine was opened was entered as mineral land in 1855 by one Beaugholtz, who prospected for several years and finally sold out to Knox and Einstein of St. Louis. Systematic prospecting was begun in 1877; and as a result a quartz vein was discovered about 100 feet above the St. Francois river. The dip having been carefully determined, a tunnel was started near the water level and driven in for a distance of 200 feet. An incline of 180 feet was also put down, from the bottom of which two or three drifts were started. Two years later the Einstein Silver Mining Company was formed and the work pushed vigorously. A large stone dam was constructed to furnish power, and furnaces and smelting works were built. Through some mismanagement the company was obliged to give up work. For a long time the mine has been idle, but recently another attempt has been made to develop the ore and a new shaft has been commenced.

Altogether 50 tons of lead were taken out of the Einstein mine and about 3000 ounces of silver.

BUILDING STONES.

No other district of similar size within the limits of the state, or perhaps in the whole Mississippi valley, has a greater variety of good stone for all kinds of constructional purposes than the area occupied by the Mine la Motte sheet. For quantity, quality and beauty, the stones that can be used for building and ornamental work are unsurpassed by any in the United States. This is attested by the fact that the stones from this, or the neighboring localities, have entered largely into the construction of some of the largest and most massive buildings in the country. Leading structures in Dallas (Texas), Omaha, St. Louis, Des Moines, Minneapolis, New Orleans, Chicago, Indianapolis, Cincinnati, Cleveland, Baltimore and other large cities have been erected wholly or in part of the Missouri stone. This stone has been transported a thousand miles for buildings reared upon the very brink of quarries the product of which is known the whole country over.

There are in the district four general classes of rock that are suitable and available for building stone. These, with their chief varieties which will be described farther on, are as follows:

Under the general term "granites" all the massive crystalline rocks of the region are known. Lithologically there are several distinct varieties which have very different properties, and which have, moreover, very different composition and structure. These various features have an important influence in the selection of a stone for structural materials.

Granite. The coarse-grained granite composes by far the greater portion of the crystallines in the district under consideration. Its area is not far from 50 square miles, most of which is easily accessible for quarrying. In color the stone is a warm red to pink; in places merging into gray. Though usually a coarse-grained rock, fine-grained varieties are of frequent occurrence. The arrangement of the constituent minerals give very beautiful effects of contrast. (Plate xii, photograph of polished surface.) The granites take a very high polish. All are very strong and are very durable. Extended examinations in thin slices under the microscope clearly indicate that the rock is in a remarkable degree free from objec tionable constituents. Both chemical and field investigations corroborate these observations. The rocks consist almost wholly of a granular aggregate of quartz and feldspar. White

mica (muscovite) is entirely absent. The amount of black mica present (biotite) which is usually one of three essential constituents and a mineral which is the first of the principal components in most granites to break down under meteoric influences, is reduced to a minimum amount and in many cases is almost entirely absent. The feldspar is, for the most part, orthoclase, the most durable of the feldspathic minerals. Accessory components liable to decompose are wanting. The great preponderance of the more indestructible constituents is also indicated by the chemical analyses.

The first two by Melville are from samples taken three miles northwest of the Silver mine, but just outside of the boundaries of the sheet. The third by the St. Louis Sampling southeast of the other locality and about two miles west of the Silver mine.

and Testing Works, is

As a quarry rock the granite has a number of features recommending it. It is jointed in such a way as to make quarrying both easy and economical. The proximity of the fractures varies at different points. In places the breaks are