The notice which, at the suggestion of Dr Brewster, is now to be laid before the Society, respecting a remarkable shower of hail which lately fell in Orkney, has been drawn up partly from conversations with Richard Caithness, a plain but intelligent country man, who possesses a small farm at Hunday in the island of Stronsa, and whose property suffered severely from the shower; and partly from subsequent correspondence with the Reverend William Taylor of Stronsa, whose house lay in the track of the cloud, and with Mr Robert Lindsay, Student of Divinity, who had an opportunity of witnessing the effects of the hail at Lopness, on the neighbouring island of Sanda, when the shower was nearly exhausted. They agree in all important particulars; but even at the risk of some repetition, their own words shall, as often as possible, be employed.

The morning of the 24th of July 1818, was, in Orkney, clear and warm, with a slight air of wind at due south.

The communication received from Dr Dyce chiefly consists of a description of a singular affection of the nervous system, and mental powers, to which a girl of sixteen was subject immediately before puberty, and which disappeared when that state was fully established. It exemplifies the powerful influence of the state of the uterus on the mental faculties; but its chief value arises from some curious relations which it presents to the phenomena of mind, and which claim the attention of the practical metaphysician. The mental symptoms of this affection are among the number of those which are considered as uncommonly difficult of explanation. It is a case of mental disease, attended with some advantageous manifestations of the intellectual powers; and these manifestations disappearing in the same individual in the healthy state.

The title which I have given to this paper, is, perhaps, faulty, and apt to lead the imagination to expect a description of the various forms of those sea-weeds which clothe the channel of the deep;—the arrangement of the species, as depending on the soil and depth of water, the food which they yield to the various creatures that browse upon them, and the protection they afford to such as take refuge among their leaves and branches. Very different, however, is the scene which I propose to describe,—a bed of peat-moss, covered by the sea at every full tide, but indicating, by the appearances which it exhibits, that its present low level is different from its original position. In other words, it is a geological phenomenon, occurring in the Frith of Tay, similar to the one observed on the Lincolnshire coast, which, in 1796, was examined by the late Sir Joseph Banks and Dr Joseph Correa de Serra, and described by the latter in the Transactions of the Royal Society of London for 1799, p. 145, under the title, “On a Submarine Forest, on the East Coast of England.” I venture to prefix the same title to this paper, which I now offer to the consideration of the Royal Society of Edinburgh, aware of its impropriety, but urged by the wish to connect similar phenomena by the common terms employed in their description.

It is no doubt already known to you, that the late Alexander Keith, Esq. of Dunottar, bequeathed the sum of L. 1000 for the purpose of promoting the interests of Science in Scotland. Having been appointed Trustees for the Management of this Fund, wa have endeavoured to appropriate it in the most advantageous manner for the advancement of Science; and we have the satisfaction of stating, that the plan which has been adopted met with the special approbation of Mr Keith himself, to whom it was communicated previous to his death.

As the Royal Society of Edinburgh is the principal Scientific Establishment in Scotland, we hereby offer to its President and Council the sum of L 600; the principal of which shall on no account be encroached upon, while the interest shall form a Biennial Prize for the most important discoveries in Science, made in any part of the World, but communicated by their Author to the Royal Society, and published for the first time in their Transactions.

Disko Island, (see Plate XV ), is situated in front of a bay in the continent of Greenland, within Davis' Strait, known by the name of Disko Bay, which is sometimes called, particularly in the old Dutch charts, Sydost Bay. This name is derived from an immense curvature, screened by innumerable islands, made in the continent by the sea. Disko Island is situated in 69° 14ʹ of N. latitude. It is distant from the continent towards the south 12 German miles; on the west and north it is surrounded by the sea of Davis' Strait; and on the east, it is separated by a narrow sound, distinguished by the name of Waygat by the Dutch, and by the Greenlanders Ikareseksoak. It stretches northward from 69° 14ʹ to 70° 24ʹ; and its greatest breadth, which is from Fortune Bay on the west, to Flakkerhuk, so named by the Dutch, on the east, is 10 German miles.

In compliance with your request, I send you a few notes of some of the principal geological facts I observed in Faroe, which may serve as a supplement to Sir George Mackenzie's and Mr Allan's accounts of these islands, which, as far as they extend, I found perfectly correct.

The Coal in Suderoe, which was not visited by them, is situated between two thick beds of hard clay, resembling the Clunch-clay of this country; to which succeed beds of trap. In some parts, pieces of petrified wood are very abundant in the superincumbent clay, and also nodules of ironstone; and in the coal, pieces of wood resembling charcoal. The coal has the same degree of inclination as the other beds, dipping towards the south-east, at an angle of about 4° or 5°; being the same as the dip in the other islands, excepting in part of Myggenæas, where it is much greater, being near 45°.

Those who have devoted much of their attention to mathematical inquiries, must have had frequent occasion to admire mire the unexpected and intimate connection which subsists between branches of their science apparently the most remote and unconnected with each other; and repeated observation will have convinced them, that no researches, however recondite or abstruse, should be neglected, because they appear to stand isolated and detached from the body of the science. These reflections appear to have been felt with strongest force, by those who have most contributed to its advancement, and were particularly insisted on by Maclaurin, in the Preface to his Geometria Organica. The present Paper will add another example, to instances already numerous, of the latent affinity between departments of mathematics, usually regarded as the most opposite.

Having heard at Port-of-Spain of an appearance that went by the name of the Mud Volcanoes, we took the opportunity when surveying the southern quarter of Trinidad, to examine them. They are situated near Point Icaque, the southern extremity of the island, on an alluvial tongue of land, that has been appended to the primitive rocks, where no doubt the land originally terminated. This appendage is several miles in length, and points directly into one of the mouths of the Oronoko, on the mainland, about twelve or fifteen miles off.

We landed nearly opposite to where we were told we should find the mud volcanoes, and after making our way about five miles through the woods, across the sandy isthmus, we came upon two plantations very pleasantly situated, amidst a group of remarkable round little hills, each from eighty to a hundred feet in height.

In plates of Rock-Crystal cut perpendicular to the axis of the prism, an unusual kind of polarisation had been observed in the colours seen along the axis. The phenomena were subsequently analysed by M. Biot, who remarked, that in some specimens of quartz, the succession of tints appeared by turning the doubly refracting prism from right to left, while in other specimens the same succession was developed by turning the prism from left to right; and he concluded from his experiments, that the quartz impressed upon the particles of light a rotatory motion, and that this property belonged to the ultimate particles of silex, and was independent of their mode of aggregation.

The same species of colours was afterwards observed, about the same time, by MM. Biot and Seebeck, in transmitting polarised light through considerable thicknesses of some essential oils, and solutions of sugar and camphor; and this new fact seemed to confirm the supposition that the colours were not dependent upon crystallisation.

The subject of poisonous fish has long been a source of puzzle and speculation to the inhabitants of the West Indies. Much has been conjectured upon it, and numerous tests and theories been proposed, which have had for a time their believers and advocates; but all have been found to be equally baseless. The author of this paper, by a narrative of what he has himself seen and observed on the subject, proposes rather to shew to the Society what it is not, than what it actually is, and thereby to clear the way for the future successful investigation of this curious and interesting phenomenon, by dissipating many erroneous notions that stand in the way of the discovery of truth.

Throughout the greater part of the West Indies, the accident of meeting a poisonous fish is a rare and extraordinary occurrence. At Barbadoes, for instance, it happens so seldom, that the majority of even the best informed inhabitants can scarcely be made to believe, that it has ever taken place amongst them.

During the summer of the present year (1820), while navigating with the ship Baffin, the icy sea in the immediate neighbourhood of West Greenland (the east side), several extremely curious appearances of distant objects, produced by the reflective and refractive properties of the atmosphere, were observed.

My dear Sir,

As I see by a notice in your Journal, No. 13., which has just reached my hands, that your attention has been occupied by the phenomena of Coloured Flames, and the Absorption of Coloured Light by Diaphanous Bodies; and that you have been successful in the very valuable discovery of a manageable flame, discharging a homogeneous yellow light of an invariable character, I shall perhaps be excused, while the contents of your paper are unknown to me more particularly, for stating some phenomena Which I have myself observed, relative to this highly interesting department of physical optics.

While examining an abandoned lead-mine in the vicinity of Stromness, in the year 1803, I found a mineral which, from its weight and appearance, I supposed to be carbonate of barytes. A few hasty experiments soon convinced me that it was a different substance; but circumstances occurring which prevented a more accurate investigation, the mineral lay neglected among the duplicates of my collection till last autumn, when having mentioned my doubts and conjectures respecting it to my friend Dr Murray of Edinburgh, I was strongly urged by that gentleman to undertake its analysis. During his short visit to Liverpool, a few preliminary experiments were begun, from which it appeared, that the mineral contained carbonate of strontia, and I have since completed its chemical examination.

The various facts concerning the radiation of caloric present a very interesting subject of inquiry, and various theories have been formed, with a view to their explanation. The principal difficulty has been to explain the facts of the apparent radiation of cold. The most simple theory with respect to these, is that proposed by M. Prevost of Geneva. He supposes, that all bodies are always radiating caloric in proportion to their temperature, and that those surfaces, which radiate least, make up for the deficiency, by reflecting most; so that the combination of reflection and radiation from any surface, when in æquilibrio with the surrounding bodies, is the same. When a body is heated, its radiation is increased, and therefore, when placed near a thermometer, it radiates more to the thermometer than it receives from it, and therefore elevates its temperature. When, on the other hand, a body is cooled, it intercepts from the thermometer near it part of the radiation of the surrounding objects, and it radiates less than it receives. The thermometer must therefore sink.

I some time ago had the honour to present to the Royal Society, a specimen of a very singular fossil which had been found in the freestone quarry of Craigleith, near this city. It presented the appearance so commonly met with in the sandstone of the coal-formation,—an impression of what has always been considered as the bark of a vegetable connected with the Palm-tribe; but it differed from any thing I had ever before seen of the kind, by having circular marks ranged in a line along the surface, being apparently the impressions of flowers or fruit. As neither of these grow directly from the stem of any plant now known, except among the Cactus genus, this impression might have been referred to it, had not the regularity of distance between these supposed flowers, pointed out the improbability; and it consequently must be referred to some one, the prototype of which is no longer known.

The size of the specimen, of which the annexed engraving is a very exact representation, is twenty-one inches in length, and about fourteen broad; the widest part of the impression measures four inches, and the diameter of the circles a little more than three.