III. Tincture of Turmeric, was not changed either by the natural water or that which had been boiled.

IV. Acetate of Lead, (newly prepared) occasioned a white precipitate in the fresh and in the boiled water. But this test when added to the water which had become turbid

by exposure, produced a dark chocolate coloured precipitate. Letters traced with transparent leadwater, became immediately legible on holding the paper over the bottle. A bright piece of silver was tarnished in fifteen minutes by submersion. A portion of quick-silver was in like manner covered with a greenish pellicle.

V. Sulphuric acid occasioned no effervescence.

VI. Solution of muriate of mercury, made no change in the fresh water: but on being added to the boiled water while hot, it produced a reddish white cloud.

VII. Muriate of lime had no sensible effect.

VII. Tincture of galls produced no change of colour. A piece of gall-nut suspended in the water during 10 days shewed no sign of blackness.

IX. Prussiate of potash. No effect. If a little sulphuric or muriatic acid be previously added to the water, the Prussian alkali developes a blue colour; but this is owing to a decomposition of the test, which (unless prepared with extreme nicety) is a triple prussiate of potash and iron.

X. Eight ounces of the water after boiling fifteen minutes was filtered. The precipitate weighed three fourths of a grain, and was entirely dissolved in muriatic acid with ef fervescence.

XI. To the filtered boiled water caustic ammonia was added, which produced a white flocculent precipitate. The unboiled water gave the same appearance with this test.

XII. The solution (No. x.) gave no precipitate with ammonia, nor with the further addition of sulphuric acid. Carbonate of potash added to the ammoniated liquor, made itturbid. A portion of the same solution to which a little

alcohol was added, when treated with the same tests, shewed the same results.

XIII. To a portion of the water concentrated by evaporation, nitrate of silver was added, which produced a light brown or flesh colour.

XIV. With nitrate of mercury a copious yellowish precipitate was thrown down both from the boiled and unboiled waters; and this after nitrate of barytes had had its full effect.

XV. A solution of muriate of barytes immediately occasioned a copious precipitate, there having been previously added to the water a small portion of muriatic acid to counteract the effect of any carbonated earth that might exist in it. Nitrate of barytes caused a similar dense precipitate, when added to fresh water, or to that previously acidulated with nitric acid.

XVI. To portions of the water, both fresh and concentrated, which had been freed from sulphuric salts by nitrate of barytes, nitrate of silver was added. A slight turbidness ensued, which after remaining two hours exposed to the light, did not change its colour from a white.

XVII. To the concentrated water a solution of pure potash was added. A thick white cloud was instantly formed, and a light precipitate collected, which was immediately discharged by a few drops of either of the mineral acids. The same experiment was repeated with water boiling hot, with the same effects, excepting that when nitric acid was added to the alkaline precipitate the water assumed a dusky brown colour and a dirty powder was deposited.

XVIII. Oxalic acid produced after a short time a milky

appearance.

XIX. Oxalate of ammonia caused an immediate precipitate in the concentrated water.

XX. Alcohol, added in equal portions to the boiled water, occasioned a crystalline deposite.

XXI. A quantity of the powder obtained by boiling the water to dryness, was dissolved in distilled water. The solution yielded a considerable deposit when treated with muriate of barytes, or with oxalate of ammonia.

XXII. To a portion of the water previously increased by a few drops of nitric acid, and boiled. Caustic ammonia was added, which gave a considerable precipitate. The supernatant water was drawn off by a syphon, and the precipitate was well washed, then re-dissolved in nitric acid, and again precipitated by carbonate of potash. This last precipitate being dried by a gentle heat, was exposed to the action of dilute sulphuric acid, but no perceptible portion of it was taken up.

CONCLUSIONS.

From the smell of the water when first opened as well as from the results of experiment 4th, it is evidently impregnated with sulphuretted hydrogen or hepatic air.

Experiment 1st, proves that no free acid exists in the water, and it also serves to shew that the sulphuretted hydrogen is not contained in very large quantities as it is well known that this air, when abundant, will slightly redden vegetable blues. The effect shown in experiment 2d, may have been produced by the presence of carbonate of lime, an inference which we find supported by experiment 10th. That the proportion of this calcareous carbonate is, however, very small, appears from experiment 5th. No alkalies either free or ærated experiment 3d. The cloud produced by muriate of mercury, (experiment 6th) indicates the presence of hydrosulphuret of lime, the existence of which is also confirmed by experiment 13th and 14th.

Experiment 8th and 9th, prove that the water contains no iron unless in a quantity not easily appreciable.

The results of experiment 12th shew that the powder obtained by boiling the water 1-4 hour, consists chiefly, if not entirely, of carbonate of lime. Experiment 15th satisfactorily proves that the water contains sulphuric acid; and that it exists in combination is also evident from experiment 1st. It It may be inferred from experiment 16th that the water is clear of muriatic salts. The effect mentioned may have arisen from hydrosulphuret of lime. The light precipitate formed in experiment 17th may have been occasioned by any of the earthy salts, formed by mineral acids. The effect shewn with the boiling water, may be attributed to the calcareous hepar. From experiment 22d we may conclude that the water contains no magnesia. The substance which last remained was probably alumine. Experiments 18th and 19th shew the existence of a large proportion of lime. These, together with the results of experiments 15th, 20th, and 21st, prove that the principal saline ingredient in this mineral spring is sulphate of lime or gypsum.

This substance, together with a considerable quantity of hydrosulphuret of lime, and a small portion of carbonate, may therefore be considered, so far as this trial has extended, as constituting the chief soluble matters in the Litchfield water, independently of its gaseous contents, a portion of which is sulphuretted hydrogen.

VIII. On NATIVE MAGNESIA from New-Jersey. By the EDITOR.

ALTHOUGH Magnesia enters into the composition of ma

ny mineral substances, yet its existence in the mineral kingdom, in an uncombined state, has, till within these few years past, been unknown.

Brogniart, in his Mineralogy, has described several minerals under the name of Magnesite, (a term he has introduced as expressive of the large quantity of magnesia they

contain) in some of which magnesia appears to exist in a pure state. Of those which approach nearest to native magnesia, are the magnesites of Piedmont, as described by Giobert in the Journal des Mines, particularly the variety from Castella Monte.* Although this mineral, as analysed by Guyton de Morveau, afforded a large proportion of carbonic acid, yet it appears from the assertion of Giobert, that when first taken from the quarry it contains no carbonic acid, but that it absorbs it after being two or three weeks exposed to the atmosphere.

The magnesite from Baudisserot, which is near Castella Monte, contains in the hundred parts, according to Giobert, 68 magnesia, 12 carbonic acid, 15 silex, 2 sulphate of lime, and 3 of water. This, like the magnesite from Castella Monte, he thinks obtains its carbonic acid from the atmosphere.

The magnesites from Vallecas in Spain, and Salinelle in France, contain no carbonic acid; they however all have a large proportion of silex: that of Salinelle, according to Vanquelin, contains 55 parts in the hundred.

Brochant mentions, as native magnesia, a substance found at Robschütz, in Moravia, by the late Doctor Mitchell, of Dublin, which, according to Dr. Mitchell's Analysis, and that of Professor Lampadius, contains nearly equal parts of magnesia and carbonic acid. Why this mineral is described as Native Magnesia, I am at a loss to determine; unless, like those of Giobert when first discovered, it contained no carbonic acid, but absorbed it after exposure to the atmosphere.

At Hoboken, in New-Jersey, on the estate of Mr. John Stevens, is found a mineral, which presents the following characters: