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pothenuse A C. This is called the Pythagorean theorem, because Pythagoras is said to have offered to the gods 100 oxen in sacrifice, in gratitude for the discovery.

The geometrical proof of this theorem is too difficult for a work of this kind, we shall therefore substitute an arithmetical solution : suppose the side A C=5, BC=4, A B=3, then 52=42452, or 25 = 16 + 9, and so it is shewn in the adjoining figure.

Corollary. Hence the square upon either of the sides A B, or BC, including the right angle, is equal to the difference of the squares of the hypothenuse and the other side: or equal to a rectangle contained under the sum and difference of the hypothenuse and the other side: thus

42 — 5— 32 or 16 = 259

42=5+3 x 5-3=8 X 2= 16. GEORGE of Cappadocia, or St. George, a saint or hero, whose name is famous throughout all the east, and by which several orders, both military and religious, have been distinguished. St. George is usually represented on horseback ; his sanctity is established in the Latin as well as the Greek church ; and England and Portugal have chosen him for their patron saint : yet who he was, or why he deserves these honours, is a profound mystery. Some deny his very existence, and reduce his effigy to a symbol of victory, while others have a faint glimpse of bim in the person of an Arian bishop of Alexandria, who flourished between the reigus of Constantius and of Julian, and who was killed in a popular insurrection of the pagan inhabitants,

GLANT'S CAUSEWAY, a magnificent production of nature, extending two miles in length along the coast of Antrim, in Ireland, and probably running under the sea as far as the coast of Scotland, since something of the same kind is met with there, and known by the name of Fingal's cave. It consists of many hundred thousands of columns of a black kind of rock, hard as marble, of about twenty feet in height, and a pentagonal, or five-sided figure. Each column stands by itself, not joining another in any part whatever ; and yet so compactly are the whole arranged that scarcely a knife can be introduced between them. What still farther fills the spectator with an amazement that increases by length of examination, is the circumstance that though almost every pillar is pentagonal in its form, and therefore presents an apparently general likeness, no two in twenty thousand have their angles and sides equal amorg themselves or to each other.

The figure of these columns, as has just been said, is almost universally pentagonal: some few, however, are of three, four, six, and even eight sides; but these are so rare that they will seldom be discovered, except by the most scrutinizing eye. The construction of the pillars is equally curious. They are not composed of single stones, but of joints, united to each other, not with flat surfaces, but by articulations, in the manner of bones, the one length having a ball which is received into the socket of the other. This mode of union is only discoverable by forcing one of the stones out of its place; but the joinings, together with the multitude of columns, give to this stupendous produc

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GIANT'S-CAUSEWAY.

11 tion of nature somewhat of the effect of gothic architecture, or of so many trunks of palm-trees. The stone is a kind of basaltes, of a close grit, dusky hue, and uncommon gravity. It clinks like iron, melts in a forge, and is impenetrable by tools.

The scene is composed of various parts, thrown together with that irregularity which distinguishes and graces the works of nature, and almost constantly stamps them with a character not to be copied. The descriptions, therefore, that have been given by several travellers necessarily differ widely from each other, as being the result of observations on separate parts of a vast and broken assemblage of objects. The principal causeway runs out in one continued range of columns, and is from twenty to thirty, and for a few yards forty, feet in breadth. Its loftiest part, which has been stated at about twenty feet, is the narrowest, ten or fifteen feet being there its utmost breadth. The columns of this varrow part incline from a perpendicular, a little to the westward, and by the very unequal height of those on the two sides, form a slope on their tops, which affords a graduated ascent from the foot of the cliff to the summit of the whole. At the distance of six yards from the cliff, the structure recovers its perpendicularity, lowers its general height, spreads to a width varying between twenty and thirty feet, and extends, at all times of the tide, to the length of one hundred yards secure from the water, and supported on columns nearly of an equal height. As far as the high-water mark, this grand and extraordinary parade, though it bas some in. clination toward the water, may be walked on with safety ; but beyond this, where it is worn with the

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surges of every tide, its declivity is so considerable, and its surface so uneven, that the foot is not to be trusted without the assistance of perpetual atten. tion. At the distance of a hundred and fifty yards,

а it turns a little to the east, and running twenty or thirty yards in this direction, buries itself at length in the sea.

At low-water, the whole visible extent of the causeway measures nearly two hundred yards: how much farther it continues is not certainly known; but from its declining appearance, it is thought to lose itself in the earth a little space beyond the spot at which it disappears. See PLATE.

GILDING, the art of covering a thing with gold, either in a foliated or liquid state. The beauty of gold has induced many attempts to imitate its appearance, and hence several methods of gilding have been invented. A coarse golden colour is sometimes given by painting, or by varnishing, without employing gold; but this is a false kind of gilding. In the manner alluded to, such a colour is given to brass and to silver, by applying upon these metals a gold-coloured varnish, which, being transparent, shows all the brilliancy of the metals beneath. Many ornaments of brass are varnished with this gold-lacquering, so called to distinguish them from those which are really gilt. Silver leaves thus varnished are put upon leather, which is then called gilt-leather. Among the false gildings, may also be reckoned that which is performed with thin leaves of copper or brass, called Dutchleaf.

: In the true gilding, gold is applied to the surface of the bodies. The gold intended for this purpose is beat into thin leaves, or otherwise divided into