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tinued to do so, the atmospheric movements being of a decidedly anti-cyclonic character, and the weather very moderate until the 19th February, when the barometer again attained a reading of 30.8 inches. This pressure was maintained until the 22nd, when the barometer commenced to fall steadily, and by the 27th February, the anti-cyclonic system of disturbance had been replaced by an ordinary and normal cyclonic movement, accompanied by a gale of wind, unsettled weather, and a correspondingly low barometer. This seemed to be the final break up of the abnormal weather, and was succeeded by the usual unsettled weather to be expected in winter.

It will thus be seen that from the 11th January till the 26th February, a period of more than six weeks in the depth of winter, there was in Western Europe a continuance of quite abnormally moderate weather, accompanied by a very unusually high barometer, the only break being for a couple of days, viz., 12th and 13th February. On the other hand, it has been ascertained from ships' reports that very heavy weather was experienced in the North Atlantic at various times during those six weeks, and that these disturbances extended as far to the Eastward as the West of Ireland in some instances.

The Rev. S. FLETCHER WILLIAMS read a paper on Some Popular Misconceptions of Darwinism." *

EIGHTH ORDINARY MEETING.

ROYAL INSTITUTION, February 6th, 1882. EDWARD DAVIES, F.C.S., F.I.C., PRESIDENT, in the

Chair. Mr. Charles Birchall and Professor Bradley, M.A., University College, were elected Ordinary Members.

* See page 133.

The Rev. H. H. HIGGINS exhibited some specimens of Lepidoptera brought from Queensland, and presented to the Museum by Mr. Reginald Cholmondeley. One of the specimens was a large Moth, Xylocantha Staceyi, not previously brought to this country; and said to be so violent in habits and disposition that, except when bred in confinement, the specimens of it known to collectors are mere wrecks.

Mr. E. DAVIES exhibited a new form of electrical accumulator, discovered by Mr. Henry Sutton, of Ballarat, Victoria. It consists of a copper cell filled with an acid solution of sulphate of copper. In this is immersed a plate of amalgamated lead, kept from coming in contact with the copper. On connecting the accumulator with a source of electricity, either a battery or a dynamo-electric machine, the sulphate of copper is decomposed, copper is deposited on the copper cell, and the lead plate is coated with peroxide of lead. When the liquid becomes colourless, the cell is fully charged. With a cell six inches square and two inches wide, a thin platinum wire was heated to whiteness, and finally fused. A small Rhumkorff's coil was also worked by means of the cell. The cell is much smaller than a Faure or Planté cell of the same power. It is very constant, and is freely put at the disposal of science students by the inventor. Mr. RICHARD STEEL read a paper on

“ Mental Science in its Quantitative Relations."

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NINTH ORDINARY MEETING.

ROYAL INSTITUTION, February 20th, 1882. EDWARD DAVIES, F.C.S., F.I.C., PRESIDENT, in the

Chair.

Messrs. Hugh Hunter and J. B. Hughes were elected Ordinary Members.

See page 193.

*

Mr. R. C. JOHNSON, F.R.A.S., gave an account of the identity of the Comet of 1880 with that of 1843 and of 1668. The difficulty was shown of assigning an exact orbit, owing to the fact that, at the only appearance when it was well seen, its trajectory was almost a straight line; for, on account of this, it was well-nigh impossible to determine whether its orbit was elliptical, parabolic, or hyperbolic. Its reappearance in 1880 has shown that the orbit is completed in a shorter time than was anticipated, and has given rise to the theory that the retardation may be so rapid, that it is possible that it may not be able to escape the powerful attraction of the sun at its next return, about the year 1897, or, at the furthest, at the next succeeding return. As its volume was, in 1843, estimated to exceed that of the earth 1,700 times (or more than that of Jupiter), it is not impossible that a collision would cause such an accession of heat that our sun might flare up in the manner in which some temporary stars have recently done, and thus cause the destruction of all life on the earth. Mr. H. L. HIGGINS read a paper on

“ The Influence of Literature upon the Growth of Religion and Law."*

TENTH ORDINARY MEETING.

ROYAL INSTITUTION, March 6th, 1882. EDWARD DAVIES, F.C.S., F.I.C., PRESIDENT, in the

Chair.

Mr. George Henry Morton was elected an Ordinary Member.

The Rev. H. H. HIGGINS, M.A., exhibited two specimens of Chalcedony containing liquid, with a movable bubble, and read the following Notes thereon :

* See page 157.

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“ These specimens were brought from Monte Video by Mr. Philip Rathbone. The larger piece contains not less than an ounce of liquid, with a large bubble ; the smaller seems to have more liquid in proportion. A third specimen is broken, showing the walls of the chamber to be, in the thinnest part, not more than one-tenth of an inch in thick

The mineral seems to have been recently discovered ; no mention of it being made in Dana's Text-book, 1880. T. W. Rudler, Professor of Mineralogy in the Royal School of Mines, informs me that he has not seen any published description of the Chalcedony enclosing water with a movable bubble.

The older mineralogists, after the fashion of zoologists and botanists twenty years ago, seem to have been too busy with the morphology of their ' finds, and with attaching to them evil-sounding names, to have given much care to the investigation of the conditions under which their costly rarities were developed. I am not a mineralogist, and make the following conjectures with much diffidence. In some cavity deep in the earth, and probably under great pressure, occurred a hollow containing a small quantity of water, above the boiling point, but kept liquid by pressure, and super-saturated with silica. On any diminution of the temperature, which might occur extremely slow, the fall of one degree occupying perhaps long ages, crystallization would set in on all the sides of the hollow holding the liquid ; and at the same time would be formed, on the surface of the water, a crystalline pellicle, from which crystals would shoot downwards and inwards. Thus would be formed a cavity enclosed on all sides, and filled with liquid. Layers of opalized quartz-chalcedony-might now be deposited externally upon the roots of the crystals, forming a cell with walls impervious to water or gas. Further diminution of temperature would enable minute quantities of gas contained in the water to assume a gaseous form, and unite in a bubble. In the broken specimen, the walls distinctly show the radial disposition of the crystals forming the lining, and the stalagmitic character of the outer rind, in which the chalcedony is deposited in layers, like the lamina of an onyx or an agate. In the large specimen, the outer surface is very interesting. It is covered with low tubercles, arranged in circles three-fourths of an inch in diameter, each circle having within it several smaller, similar, concentric circles. The cavity is not strong enough to withstand any considerable bursting pressure from within. It is possible, however, that the shrinkage of the contents of the cavity from cold may have maintained the equilibrium between outside and inside pressures. Although the tank-forming chalcedonies do not appear to have been described, quartz crystals, with minute drops and movable bubbles enclosed, have long been common in all collections of minerals. John W. Judd, F.R.S., in his admirable work on Volcanoes, gives the best, almost the only, description I have seen of them. The liquid may be water, a hydro-carbon, or even carbon dioxide. That it may be the last has been proved by spectrum analysis, and by the test that when the crystal is heated to 86° or 90° Fahrenheit, the bubble disappears, that temperature being, of carbonic dioxide, the critical point above which no pressure can keep it in a state of liquidity. Still more remarkable is Mr. Judd's account of miscroscopic cavities containing liquid, in which the bubble is in constant motion, pursuing a spiral track from end to end of the cavity. For the only attempt at explanation of this motion yet given, Mr. Judd's work may be consulted ; and no one will regret having read the book from the first to the last page. All the cavities of which Mr. Judd speaks are very minute, and it is evident that the tank-forming chalcedonies are constructed in some manner to which the quartz crystals containing drops can afford no sufficient clue; though, as in my own case, Mr. Judd's beautiful researches

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