into water. If lime-water be formed, it will become turbid by blowing through it by means of a quill: in this case, too, the calculus will be that of oxalate of lime. It may be merely added, if that under examination be the triple calculus, it will yield volatile ammonia, on treatment with caustic potassa. I need not particularize; and these are the general indices. I always am, with the highest respect, gentlemen,

Your very faithful and obedient servant,

J. MURRAY. P.S.-I notice a slight error in my paper on "Solution developed from the Action of Sulphuric Acid on Chlorate of Potassa in Water." It dissolves gold leaf very readily; the foil appearing finally a very thin perforated film having lost all its metalline appearance. Blue colours are promptly discharged. Sodium does not kindle when projected on its surface, though potassium inflames very readily.

J. M.

XCI. Note of some Experiments on the Vapour of Sulphuric Ether. By JOHN MURRAY, F.L.S. M.W.S. &c. &c.

To the Editors of the Philosophical Magazine and Journal. GENTLEMEN, I AM not aware that the following phænomena are any where recorded; many of the experiments detailed are, perhaps, sufficiently curious and interesting to merit a place in your Journal.

The copious and continued extrication of inflammable vapour from the surface of ether is remarkable, and may be made subservient to a chain of experiments illustrative of its physical and chemical character.

The vapour may be poured in an invisible form from one vessel to another, as in the ease of carbonic acid An iggas. nited taper will be the test of its presence. In like manner the vapour may be laved or pumped out into other vessels, or transferred by a wide stop-cock laterally, or through a funnel.

The vapour, however, being poured into a glass funnel with a stem eight inches long and the diameter of the bore 1-8th to 1-16th inch diameter, did not flow out, but remained in the funnel above.

The sulphuric ether vapour poured on carbonic acid gas, mingles with it, and from this uniform diffusion, the gas, &c. burn with a diluted blue flame to the bottom of the cylinder containing them.

Mixed with hydrogen, it burns with a lambent blue flame. With nitrous gas, ignition does not produce explosion. It

burns

burns tranquilly and in all respects like a mixture of nitrous gas and hydrogen, having an increased illuminating power, and of a green colour.

Equal parts of the ethereal vapour and nitrous oxide burnt with a flame resembling the last in colour, but the ignition was rapid and approximating the explosive range.

The vapour does not seem to diffuse in olefiant gas,- -this last burning with its usual illuminating effect, and it is succeeded by a blueish flame, such a one as seemed to be characteristic of the vapour.

The ethereal vapour poured on chlorine gas in day light, gives rise to the immediate formation of clouds of muriatic acid gas, accompanied by the exhalation of a kind of spray from the bottom of the vessel.

Equal volumes of sulphuric ether vapour and ammoniacal gas burn tranquilly to the end, with reddish green flame.

Equal volumes of vapour and cyanogen diluted the flame, and made it apparently more luminous.

Equal parts by bulk of the vapour and sulphuretted hydrogen burn with a lambent blue flame: little sulphur is deposited, and the combustion gives rise to the odour of garlic.

It inflames on the surface of naphtha, water, &c. Poured on the surface of nitric and muriatic acids, it burns with slight alteration of tint.

On ammonia in solution the flame has a reddish tint. The combustion from the surface of sulphuric acid is more rapid, somewhat of an explosive kind, and the flame is of a red cast. Oct. 7, 1822. J. MURRAY.

P.S. Gold-leaf was immersed in the vapour of sulphuric ether, and allowed to repose for four weeks, without any perceptible change having been superinduced. Thin slips of caoutchouc exhibited no alteration whatever in eight days: a small quantity of distilled water was at the termination of this period added. In some days the slips were slightly blanched, the edges being most whitened. In the change here produced there seemed an approximation to the consistency of leather.

I shall only take leave to add, that the thin slips of caoutchouc referred to were obtained by inflating, by means of a condenser, small bottles of Indian rubber in the way described by Mr. Forster.—I have thus expanded bottles of caoutchouc, from the size of a walnut to the diameter of six inches and more. I have found strips of the caoutchouc so extended, admirable valves for the condenser of my gas blowpipe."

XCII. True apparent Right Ascension of Dr. MASKELYNE'S 36 Stars for every Day in the Year 1823, at the time of passing the Meridian of Greenwich. Calculated from BESSEL'S Tables of 1820. Vol. 60. No. 296. Dec. 1822.

3 L

1823.

1823.

13 15 14 7

1823.

XCIII. On

XCIII. On the Expansive Force of Steam at different Temperatures. By PHILIP TAYLOR.

To the Editors of the Philosophical Magazine and Journal.

Bromley, Middlesex, Dec. 26, 1822.

GENTLEMEN, MUCH interesting discussion having lately taken place on the expansibility of steam, I shall feel pleasure if I can in any degree contribute toward a more correct knowledge of the physical properties of this important agent.

Some years since, I proposed a safe and simple mode by which the heat of compressed steam might be employed, to any extent, in various manufacturing processes.

In this application of steam, it became necessary to determine what precise temperature would result from its different degrees of compression; for in many cases it was desirable to employ it as the medium for conveying heat to solutions of saline substances and sugar, which require high degrees of heat for their ebullition.

Finding that my practical results did not accord either with the experiments given by other writers, or with the theories deduced from them, I was led to form a Scale (Plate VI.) which might show the expansive force consequent on each degree of temperature, from 212° to 320° Fahr.

As this Scale was intended to exhibit the force of steam above the point at which the atmospheric pressure balances it, I have placed my zero at 212°, and given the forces produced by each addition of temperature in inches of mercury; and in order that it might be rendered more convenient for use, the divisions are reduced to one-fourth of their actual magnitude. I have also in another column given the pressure on a square inch at each degree of temperature-assuming that 21 inches of mercury of sp. gr. 13.50, are equal to one pound per square inch. The rapidly increasing series of the forces compared with the regular increments of heat, is at one view exhibited on this Scale, in a manner which I hope will be interesting to the man of science, and useful to those who are like myself engaged in the practical application of the force and heat of steam.

This Scale was formed by the means of an apparatus likely to render my experiments as correct as any can be, which depend on the indications of thermometers; but I have hitherto hesitated in publishing it, from its great variance with those Tables already given by men of science,

Repeated experiments having led me to believe that my results are correct, I send it for your insertion :-at the same time I wish to observe, that I have not endeavoured to make