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placed on the accuracy of the observations, that the annual variation of the dip in this part of the world is greater now than it was thirty or forty years since.

It is a curious consideration, that taking Mr. WHISTON'S determination as the dip in 1720, 75° 10′, we obtain, between the years 1720 and 1774, an annual diminution of 3'.05, which differs only three hundredths of a minute from the rate which has now been found for the succeeding forty-seven years."

Some Positions respecting the Influence of the Voltaic Battery, in obviating the Effects of the Division of the Eighth Pair of Nerves. By A. P. WILSON PHILIP,M.D.

On some Alvine Secretions found in the Colon of a Young Man after Death. By J. G. CHILDREN, esq. (See our third volume, page 145.)

On the Concentric Adjustment of a Triple ObjectGlass. By W. H. WOLLASTON, II.D.

On a new Species of Rhinoceros, found in the Interior of Africa. By Sir E. HOME. (See some account of this animal in our second volume, page 466.)

Observations on a Comet seen at Valparaiso. By Capt. BASIL HALL.

Elements of Capt. BASIL HALL's Comet. By J. BRINK, esq. D.D.

On the Electrical Phenomena exhibited in Vacuo. By Sir HUMPHRY DAVY.

"Is electricity a subtile elastic fluid? or are electrical effects merely the exhibition of the attractive powers of the particles of bodies? Are heat and light elements of electricity, or merely the effects of its action? Is magnetism identical with electricity, or an independent agent put in motion or activity by electricity? Queries of this kind might be considerably multiplied, and stated in more precise and various forms: the solution of them, it

must be allowed, is of the highest importance; and though some persons have undertaken to answer them in the most positive manner, there are, I believe, few sagacious reasoners who think that our present data are sufficient to enable us to decide on such very abstruse and difficult parts of corpuscular philosophy.

"It appeared to me an object of considerable moment, and one intimately connected with all these queries, the relations of electricity to space, as nearly void of matter as it can be made on the surface of the earth.”

In consequence, Sir Humphry undertook some experiments relative to the subject, which we cannot detail, but we present our readers with his most important conclusions.

"It is very evident, from the general results, that the light (and probably the heat,) generated in electrical discharges, depends principally on some properties or substances belonging to the ponderable matter through which it passes; but they prove likewise that space, where there is no appreciable quantity of this matter, is capable of exhibiting electrical phenomena: and under this point of view, they are favourable to the idea of the phenomena of electricity being produced by a highly subtile fluid or fluids, of which the particles are repulsive with respect to each other, and attractive of the particles of other matter.

"In common cases of electrical action, the quantity of the heat generated by the annihilation of the different electrical states, depends upon the nature of the matter on which it acts; and, in cases where electrical sparks are taken in fluids, vapour or gas is always generated; and in elastic fluids, the intensity of the light is always greater, the denser the medium. The luminous appearances, therefore, it is evident from all the statements,

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must be considered as secondary; whilst the uniform exertions of electrical attractions and repulsions, under all circumstances, in rare and in dense media, and in vacuo, and with respect to solids, fluids, and gases, point them out, (whether they be specific affections of a subtile imponderable fluid, or peculiar properties of matter,) as primary and invariable electrical phenomena.”

Croonian Lecture. On the Anatomical Structure of the Eye, illustrated by microscopical drawings; executed by F. BAUER, esq. By Sir E. HOME. The plates which relate to this article are seven in number, and are highly deserving the attention and study of the anatomist.

On a Derangement of the Mural Circle at the Royal Observatory. By JOHN POND, esq.

On the Finite Extent of the Atmosphere. By W. H. WOLLASTON, M.D.

On the Expansion of a Series of the Attraction of a Spheroid. By JAMES IVORY, M.A.

On the late extraordinary Depression of the Barometer in December, 1821. By LUKE HOWARD, Esq.

By Mr. Howard's observations made at TottenhamGreen, it appears that the barometer was at its lowest point of depression on the 25th of December, at 5 a.m. when it stood at 27.83.

The rain fallen in November and December, 1821, was 10.10 inches, a quantity without any recorded precedent for the same space of time at London.

On the Anomalous Magnetic Action of Hot Iron, between the White and Blood-red Heat. By PETER BARLOW, Esq. This is a curious paper, but we have not room for any particulars.

Observations for ascertaining the Length of the Pendulum at Madras, East Indies, lat. 13° 4' 9", N. with

the conclusions drawn from the same. GOLDINGHAM, Esq.

By JOHN

Account of an Assemblage of Fossil Teeth and Bones of Elephants, Rhinoceros, Hippopotamus, Bear, Tiger, Hyæna, and sixteen other Animals, discovered at a Cave in Yorkshire in 1821, with a comparative view of five similar caverns in various parts of England, and others on the Continent. By the Rev. W. BUCKLAND. (See our third volume, page 209.)

On a curious Appearance lately observed upon the Moon. By the Rev. F. FELLOWS.

On the difference in the Appearance of the Teeth and the Shape of the Skull, in different species of Seals. By Sir E. HOME.

Royal Society of Edinburgh.

(Continued from our last.)

1822. Jan. 7.-Account of a new species of Double Refraction, by Dr. BREWSTER.-An account of a singular Case of Uterine Irritation, and its effect upon the Mind, by Dr. DYCE.

Jan. 21. Biographical Sketches of some of the earliest Scottish Lawyers, preceded by a view of the political condition of Scotland during the latter part of the sixteenth century, by Mr. P. F. TYTLER.

Feb. 18.-On the specific heat of the Gases, by Mr. HAYCRAFT. From the experiments detailed, it appears that the specific heat of all the gases enumerated is the same when they are freed from moisture; and that, when they are combined with water, they have their capacities affected in certain regularly ascending ratios, as, 1, 2, 3, and 4, dependent, it appears, on the proportion of water with which they are combined.

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March 4.-Notice relative to some Surgical Instruments found at Pompeii, by Dr. BORTHWICK.-On the structure and properties of a vegetable membrane known by the name of Rice Paper, by Dr. BREWSTER.-A notice of Mr. Barlow's discoveries respecting the Magnetism of redhot Iron.

March 18.-A continuation of Mr. Tytler's Biogra phical Sketches of some of the earliest Scottish Lawyers.. April 1.—An inquiry into the nature of Atmospheric Pressure, by R. SAUMAREZ, esq.

April 15.-Description of a Monochromatic Lamp, with Observations on the Composition of different Flames, as modified by Reflexion, Refraction, and Combustion, by Dr. BREWSTER. By illuminating microscopic objects with this lamp, a distinctness and perfection of vision is obtained, which extends widely the power of the microscope, so that delicate structures and minute organizations, which are beyond the reach of observation when common light is employed, may be readily examined.→ Observations on the Errors in the Sea-rate of Chronometers, arising from the Magnetism of their Balances; with suggestions for removing this source of error, by Capt. SCORESBY, jun. Three means are here suggested to lessen or obviate the anomalous action of the balance. 1. To employ a substance in the construction of the balance without magnetical properties. 2. To free the balance from any magnetism accidentally acquired. 3. To prevent the unequal action of the magnetic influence by giving to the chronometer a fixed position, as regards the magnetic meridian.-To apply the first method it is proposed to make the balance of platinum; to accomplish the second object it is proposed, that the flat surface of the balance be ground and polished in the plane of the magnetic equator; to effect the third object, the chro