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take place till the mass had returned to the state of rest, but before the separation took place between the clay and the water. The structure of the frozen mass varied in different experiments. In every case, however, frozen mud and frozen clear water could be distinguished from each other. But the latter did not occur as a stratum at the upper part of the mass, but was distributed through the substance of the frozen mud.

1. The most common appearance was like that of small quartz veins traversing in different directions a siliceous slate. The same as in hand specimens of siliceous slate, when two of the quartz veins meet one another, they traverse one another, shift one another, or mutually cut each other off, &c. was observed distinctly in the present instance. The principle that the traversing vein is newer than the one traversed, could not be easily demonstrated to be correct in these ice veins in the frozen mud; nor could the idea of the contemporaneous formation of veins with the surrounding rock be admitted as unconditionally correct. In these ice veins there was apparently a real cutting across of one vein by another, so that the traversed vein beyond the traversing pursued its original course, or was diverted somewhat from its position, but more frequently one was completely cut off by the other. Often we could suppose a true wedging out of such a vein without a previously existing empty fissure promoting its formation.

2. Often the water-ice was distributed through the frozen mud like the quartz in the felspar of graphic granite. The surface formed by cutting and polishing exhibiting, like the latter Hebraic, Arabic, and Chinese characters; and these were still more characterised on the dark surface of the mud, than the greyish-white quartz on the whitish felspar.

3. Another mode of distribution of the water-ice in the frozen mud, was its forming vertical plates, which were so grouped that the surface of the mass of mud on its middle section, resembled a concentrically radiated crystalline mass, the rays diverging from the centre outwards. Several of these groups of rays were observed. Each ray projected to a considerable height above the surface of the mud.

During the formation of the veins, I sometimes observed also that of hollow spaces. These were enclosed by three or more

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ice veins, which penetrated obliquely downwards, partly to the bottom of the vessel ; they had a breadth of from half to three quarters of an inch, and were quite empty of the frozen mud.

The frozen mud, separated as much as possible from the transparent ice, gave, when thawed, a moist mud, so that crystallization had produced no more complete separation than simple rest; but the ordinary separation of the water from the mud was produced in a much shorter time than by the mere operation of specific gravity in the mechanical mixture.

With regard to the causes of the three different appearances that I have enumerated, they appear to me to depend upon differences in the excess of water in the mud, on the temperature of the mass before it is exposed to congelation (sometimes boiling water was used), and especially the rapidity of the congelation. Farther I can give no explanation.

Account of the Introduction of the Wood-Grouse or Capercailzie

(Tetrao Urogallus) to the Forest of Braemar. By JAMES Wilson, Esq. F.R.S.E., M.W.S., &c. Communicated by

the Author. The almost recent extinction in Britain of the largest European bird of the gallinaceous order, is a remarkable fact in the

geographical history of the species. Its reintroduction is also a circumstance of sufficient interest to deserve a detailed record.

The wood-grouse or capercailzie, was formerly a well-known and frequent inhabitant of the Scottish forests. It still occurs in considerable abundance among the wooded and alpine districts of Europe, especially in Scandinavia. It is rare in France, well-known in Germany, not unfrequent in Switzerland. It spreads through Russia into Siberia, and is very numerous in several districts of the north of Asia. It seems always to prefer mountainous forests, and is rarely met with in plains or flat countries, however richly wooded. Its favourite trees are pines, birch, and juniper. It feeds on the fruit of the last-named plant, and on the buds and tender sprays of the two former. Colonel Montagu found the crops of two females which he examined, to contain a species of berry similar to the cranberry, called in Norway Tytteboer; and the tops of that plant, toge

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ther with sprigs of the common heath, appeared to have been swallowed in considerable quantity. The gizzard was extremely strong and muscular, and contained a large mass of pebbles intermixed with the macerated food * Many other alpine and woodland plants, no doubt, minister to its wants, and, in common with the rest of its order, insects of various kinds

may

be presumed to be sought after, especially by the young.

These birds are of polygamous habits, and consequently do not pair. During the breeding season, which commences as soon as the buds begin to expand, and continues throughout the rapid northern spring till the forests are clothed in their freshest green, the male is frequently seen perched on some tall pine, where he moves backwards and forwards, uttering at the same time a peculiar cry, which seems to attract the neighbouring females. His head, on these occasions, is red and swollen ; his wings dependent, and his neck extended. His cry is said to commence with a loud explosion, which is followed by a noise like that of the whetting of a scythe. This is heard at a great distance, and, as soon as the females are collected around the tree, the male descends from his “ high estate,” and joins their company t.

The last capercailzie recorded to have been killed in Scotland, was shot, about fifty years ago, near Inverness. For a considerable time anterior to that period, it had been of extremely rare occurrence, and, although a solitary remnant of the ancient stock may have contrived to maintain a precarious existence for a few succeeding years in some obscure recess of the umbrageous forests of Braemar or Rothiemurchus, it can scarcely be doubted that the species, ere long, ceased to exist as indigenous to Britain. It was known to have been extirpated from Ireland at a considerably earlier period.

When we consider the great size and beauty of this species of game, and its value as an article of food, we need not wonder that various attempts have been made to naturalize it for the second time in Scotland. I shall confine my present notice to the individuals which I have myself had an opportunity of observing

* Supplement to the Ornithological Dictionary,

+ Journal Economique, April 1753. VOL. XIII. NO. XXV. --JULY 1832.

L

I had last summer the pleasure of accompanying my scientific friends, Professor Graham and Dr Greville, on a botanical excursion to the Valley of Clova. The discovery of Astragalus alpinus, till then unknown as a British plant, and of other interesting rarities, rewarded their zeal, and has been elsewhere recorded* For myself, I chiefly plied the angler's trade, and had the satisfaction of providing my friends and their followers (Professor Graham being accompanied by a detachment of his class) occasionally with an agreeable addition to their dinner in regions where there were very few loaves, and (but for my exertions) no fishes. We afterwards crossed the Grampians, skirting the “ dark Loch-na-gar” and other fine mountain masses of that neighbourhood, and, descending to the banks of the Dee, took up our residence for a time at the Castletown of Braemar.

I was wading down the Dee one fine afternoon, a little below Mar Lodge, and with a lighter pannier than usual, when I heard the cry of a bird to which I was unaccustomed, and my bad success in that day's angling induced me the more readily to diverge from the “ pure element of waters," to ascertain what this might be. I made my way through the overhanging wood for a few hundred yards, and soon after reaching the road, which runs parallel with the river on its right side, I observed a wooden palisade, or enclosure, on the sloping bank above me. On reaching it, I found it so closely boarded up, that I had for a time some difficulty in descrying any inmates, but my eye soon fell upon a magnificent bird, which at first, from its bold and almost fierce expression of countenance, I took rather for some great bird of prey than for a capercailzie. A few seconds, however, satisfied me, that it was, what I had never before seen, a fine living example of that noble bird. I now sought the company of Mr Donald Mackenzie, Lord Fyfe's gamekeeper, the occupant of the neighbouring cottage. He unlocked the door of the fortress, and introduced me to a more familiar acquaintance with its feathered inhabitants. These I found to consist of two fine capercailzie cocks and one hen, and the latter, I was delighted to perceive, accompanied by a thriving family of young birds, active and beautiful. I made various inquiries on the spot; but the fatigues of angling, and of entomologising combined, prevented my writing down the result at the time, although I have still a distinct recollection of the leading facts *.

* See this Journal, October 1831, p. 373.

It was, however, with great pleasure that I availed myself, at an after period, of Sir Thomas Dick Lauder's obliging offer to convey a series of queries to Mr Cumming, Allanquoich, Braemar, Lord Fyfe's factor, from whom I received the substance of the following information.

The first importation of these capercailzies arrived from Sweden about the end of the year 1827, or early in January 1828. It consisted of a cock and hen, but the hen unfortunately died after reaching Montrose Bay. As the male bird alone arrived at Braemar, the experiment was judiciously tried of putting a common barn-door fowl into his apartment during the spring and summer of 1828. The result was, that she laid several eggs, which were placed under other hens, but from these eggs only a single bird was hatched, and when it was first observed it was found lying dead. It was, however an evident mule, or hybrid, and shewed such unequivocal marks of the capercailzie character as could not be mistaken.

The second importation likewise consisted of a cock and hen, and arrived safely in this country in January or February 1829. The female began to lay in the ensuing April, and laying in general an egg every alternate day, she eventually deposited about a couple of dozen. She shewed, however, so strong a disposition to break and eat them, that she required to be narrowly watched at the time of laying, for the purpose of having them removed, for otherwise she would have destroyed the whole. In

During our excursion we generally passed over the ground more rapidly than was consistent with entomological observation. The objects sought for by the botanist are generally of larger size, and being also lovers of light and sunshine, they are more easily distinguished than most of the insect tribes, so many of which court concealment and the shade. I was, however, fortunate in obtaining near the Spittal of Glenmukk the scarce heath-butterfly Hippar. chia Typhon, which I had never before seen alive in Scotland ; and in open glassy glades, among the woods which skirt the right bank of the Dee, between Abergeldy and Invercauld, I captured the rare and beautiful Hipparchia Blandina, commonly called the Scotch Argus, a species hitherto found chiefly in the island of Arran, and not previously known to occur so far north on the mainland. Of the rarer Diptera, Pedicia rivosa may be mentioned as not unfrequent among the woods of Braemar.

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