responding diameter to Dupont's well would, according to just and reasonable calculations, furnish about two million gallons in twenty-four hours; also the elevation of the water above the surface is greater than that of any other artesian well, and it is only exceeded in depth by the St. Louis well, and that to an extent of one hundred and thirteen feet. The water comes out with considerable force from the fiveinch opening, and a heavy body thrown into the mouth of the well is rejected almost as readily as a piece of pine wood. By an approximate calculation its mechanical force is equal to that of a steam-engine with cylinder ten by eighteen inches, under fifty pounds' pressure, with a speed of fifty-five revolutions per minute, a force rated at about ten-horse power. The top of the well is now closed, and the water conducted about thirty feet to a basin with a large jet d'eau on the center, from which there is a central jet of water forty feet in height, with a large waterpipe, from which the water passes in the form of a sheaf. When the whole force of water is allowed to expend itself on the central jet, it is projected to the height of from ninety to one hundred feet, settling down to a steady flow of a stream sixty feet high. Temperature of the Water.-The water as it flows from the top of the well has a constant temperature of 761° F., and is not affected either by the heat of summer or the cold of winter. The temperature at the bottom of the well is several degrees higher than this, as ascertained by sinking a Walferdin's registering thermometer to the bottom, which indicated 821° F. Taking as correct data that the point of constant temperature below the surface of Louisville is the same as at Paris-namely, 53° F.--at ninety feet below the surface we have an increase of one degree of temperature for every sixty-seven feet below that point. The increase in Paris is one degree for every sixty-one and two tenths feet. The temperature of the water is sufficient for comfortable bathing during most of the yeara circumstance that will be of considerable importance if it ever be turned to the use of baths. The reason of the difference of six degrees between the water at the bottom of the well and at the top is that the iron pipe leading from the surface to the rock passes through a stratum of water sixty feet thick, having a temperature of fifty-seven degrees. The Source of the Water.-The question naturally arises, if the vein of water supplying this well has a connection with some distant source higher than the surface of Louisville, where is that source? From all that we have been able to learn of the geology of this county, taking Louisville as a center, the first rocks encountered corresponding to the sandstone (in which the water of the artesian well was struck) are in Mercer, Jessamine, and Garrard counties, near Dix Creek, to the east of Harrodsburg. The rocks there are said to be cavernous and water-bearing. The elevation is about five hundred feet greater than Louisville, and about seventy-five miles in a straight line from this city. This being the most probable source of the water, whence come its mineral constituents? These are obtained from the rocks through which it percolates in its way from its source to the point below Louisville where it has been tapped, and where it will doubtless flow in undiminished quantity for centuries to come, as wells having such deep sources as this are usually inexhaustible. Nature of the Water.-The water is perfectly limpid, with a temperature, as already stated, of 7610, which will be invariable all the year round. Its specific gravity is 1.0113. The solid contents left on evaporating one wine gallon to dryness are 915 grains, furnishing on analysis Chloride of sodium (common salt).. Chloride of calcium... Chloride of magnesium...... Chloride of potassium. Chloride of aluminum. Sulphate of lime..... Sulphate of magnesia... Grains. 621.5204 65.7287 14.7757 4.2216 1.2119 .1012 72.2957 29.4342 77.3382 1.8012 3.2248 Bicarbonate of soda.... 2.7264 The analysis was performed by the usual methods; but as chloride of lithium was sought for and found, it may be of interest to detail the method of research in this particular, as a guide to similar investigations of other mineral waters in this country. Ten gallons of water were evaporated to about two pints (there was an abundant deposition of salts); to this was added one gallon of ninety-five per cent. alcohol; it was then thrown on a filter, and the salts on the filter washed with alcohol of the same strength; the filtered liquor was evaporated nearly to dryness; in the present instance the residue consisted of a few ounces of a thick, syrupy liquid; to this was added one pint of absolute alcohol; additional salts were precipitated; the liquid was again filtered and evaporated nearly to dryness; to it were added eight ounces of distilled water and two ounces of milk of lime (pure lime made by igniting carbonate of lime prepared by carbonate of ammonia); the lime was added for the purpose of precipitating the magnesia and alumina; again filtered and washed; the filtered liquid was somewhat concentrated, and while warm carbonate of ammonia was added to precipitate the lime; it was then filtered and evaporated to about a fluid-ounce and treated with a little lime-water and carbonate of ammonia alternately, to insure the absence of the last traces of magnesia and lime. Before going further it would be well to state that the treatment of alcohol separates the great mass of salts that are held in solution by the water, and which interfere with the detection of so minute a constituent as the lithium salt; by the alcohol we reduce the salts to small amounts of chlorides of magnesium, aluminum, calcium, sodium, pótassium, and lithium; by the lime the first two are got rid of, and by the carbonate of ammonia the lime is precipitated. The solution, now containing the chlorides of sodium, potassium, lithium, and ammonium, is evaporated to dryness, and the residue heated to dull redness, by which the ammonia salt is expelled and a little organic matter destroyed; the residue is next dissolved in water, and a drop or two of the liquid tested for a sulphate; should this be present it must be got rid of by exact neutralization with chloride of barium (a slight excess of the chloride of barium will not interfere with the other steps in the analysis). In the examination of the water in question no trace of sulphate was found at this stage of the process; so it was again evaporated to dryness in a small capsule over a water-bath; there were now a few grains of residual matter. To this was added an ounce of a mixture of equal parts of pure ether and absolute alcohol, the capsule was covered with a small receiver and allowed to stand for eighteen hours, the liquid was then thrown on a small filter, and the filter washed with a little of the mixture of ether and alcohol. The alcoholic ether solution, evaporated to dryness, furnished the chloride of lithium, recognized by its well-known characteristics. Although this process requires considerable time and some careful manipulation, its results are both accurate and satisfactory. The evaporation of two hundred gallons of the water, and the examination of the concentrated mother-water, enabled me to detect rubidium and cæsium by the aid of the spectroscope. The water of this artesian well has very valuable medical properties, and those readers who are curious to examine into these points will obtain all the required information by sending to Louisville for the medical report. 14 REMARKS ON THE ALKALIES CONTAINED IN THE MINERAL LEUCITE AND ON THE COMPOSITION OF WARWICKITE. In examining recently many of the silicates containing alkalies my attention has been called to leucite, and it is on that mineral especially that I would now remark, reserving for another time my observations on the other silicates. The specimens of leucite examined came from four localities, Vesuvius, Andernach, Borghetta, and Frescati. They were about as good specimens as are obtained from those localities. although all of them were not equally pure. The alkalies found in each calculated as potash were The specimen from Andernach was analyzed for the silica. etc., and found to contain silica 54.75, alumina 23.08, and 1.55 of oxide of iron; this last seemed to be mechanically disseminated through the crystals. I say above in relation to the alkalies "all calculated as potash," for the reason that there is a notable quantity of rubidium and cæsium present in all the specimens above mentioned. In fact, by the method adopted in testing for these alkalies, abundant indications are obtained of the presence of rubidium and cæsium (the last not so readily) even when operating on but half a gramme of the mineral. I am now engaged in working out a method of estimating quantitatively rubidium and cæsium in the presence of other alkalies; by this method, not yet perfected, the quantity of these alkalies in leucite is found to be about nine tenths of one per cent. of the entire mineral. Of course it is not at all remarkable that the potash in the different specimens of leucite should be the same; but it is a |