Mr. Wilde's discovery at Lagore was followed by other discoveries of the same kind elsewhere in Ireland, so that in 1857 the existence of about 50 C. had been ascertained; and every succeeding year had seen an increase of the number. They show several varieties of construction. The island at Legere is a type of the purely artificial cran noge. But most frequently the crannoge was partly natural. An islet just level with the water, was raised artificially a foot or two above it. An islet too small to be a convenient habitation, or too easy of landing to be a place of defense, had its area arti ficially enlarged, or its banks artificially strengthened, generally by piles or stockades, but occasionally by heaps of stones. The space thus incldsed is generally a circle of from GO to 80 ft. in diameter; but in some cases the inclosed larger, and of an oval shape. The piles are generally of oak, mostly young trees, from 4 to 9 in. broad, still bearing marks of the hatchet; usually a single row has been considered enough, but there are instances of two, and even of three rows. It would Rein that originally the piles had risen several feet above time water, and it has been supposed that they were interlaced with branches placed horizontally, so aS to form a screen or breastwork. The area within the stockade is sometimes wholly or partially covered with a layer of round logs, from 4 to 6 ft. long, having stones, clay, or gravel above them. Fragments of oak-framing, with mortises and cheeks cut in them, have been found within the piles. In almost every instance, is few flat stones, apparently serving as a hearth, have been observed near the middle of the inclosure; in several C., two or three hearths have been met with. In some cases, a causeway leads from the island to the mainland; but in general the crannoge was to be reached only by boat, and scarcely any crannoge has been discovered without the remains of a primitive canoe, hollowed out of the trunk of an oak, being found beside it. In at least one crannoge, a pier or jetty projected from the island; it was a double row of piles and stretchers, running parallel to each other at a distance of about 8 ft., and supporting a platform of logs. On almost every crannoge one or two querns (q.v.) have been found, along with anes of oxen, deer, goats, and swine, horns of cattle, deer, sheep, and goats, boars' tusks, and sharpening stones! fragments of pottery, and articles of stone, bone, horn, wood, glass, copper, bronze, brass, and iron, are of somewhat rarer occurrence.,, Many of the C. had been sub marged by the gradual rise of the lakes in which they stood, so that their existence only became known as the great drainage•works of late years reduced the waters to their old level.
In a section of the crannoge in Ardakillin lough, near Stokestown, in the county of Roscommon, the upper surface of the crannoge was formed of a layer of loose stones, surrounded by a wall, partly supported by piles. The stones rested on the natural clay, peat, and boulders of the island, in digging through which strata of ashes, bones, and logs of timber were met with. The stockades were of oak; the oblique or slanting stockade is a girdle of sheet-piling which quite encircled the crannoge.
Of one of two C. in Drumaleague lough, in the county of Leitrim, the circle within the ring of stockades is 60 ft. in diameter; in some places there are two, and in others, three rows of stockades; and within this outer ring, there are groups of piles, some of them arranged apparently for some special purpose. The oblong space in the middle, marked A, is covered by a rude platform of round logs, chiefly of alder, from 4 to 6 ft. in length; it was prolfably the floor of the log-house, which was the chief or only dwelling-place on the islet. B shows where the hearth stood—a collection of stones, still retaining traces of fire; C marks a heap of stiff clay; D, the root of a large tree nearly buried in the peat, the surface of the wood being beveled off with a hatchet, so as to form a sort of table, under which was found a heap of bones, apparently of deer and swine.
The Irish annals, it has been seen, make mention of C. as early as the 0th c., and they figure in history down to the middle of the 17th century. The crannoge of lough Lynch, in Antrim, is shown as the birthplace of Colkitto, a chief who figured in 3Iontrose's wars, and has found a place in one of 31ilton's sonnets. The crannoge of
Roughan lake, near Dungannon, was the last retreat of sir Phelim O'Neil in 1641. Two years later, there is record of an attempt to flood the crannoge of Loughinsholin, in the county of Londonderry, by turning a stream into the lake, and d up its outlet. This attempt failed; but in 1645 the garrison were compelled by hunger to give the cran noge to the flames, and make their escape. In 1567, an agent of the English government, who was asked what were the castles of the O'Neil, wrote in reply: "For castles, he trusteth no point thereunto for his safety, as appeareth by the razing of the strongest castles of all his countries; and that fortification that he only dependeth upon is in cer tain fresh-water lochs in his country, which from the sea there comes neither ship nor boat to approach them: it is thought that there, in the said fortified islands, lieth all his plate (which is much), and money, prisoners, and gages [i.e., hostages]; which islands have in wars heretofore been attempted, and now of late again by the lord-deputy there, sir Harry Sydney, which for want of means for safe conduct upon the water bath not prevailed." While archmologists were still exploring the C. of Ireland, structures of a similar kind were discovered in the heart of the European continent. The winter of 1853-54 was one of the driest that had been seen in Switzerland, and the lakes sank to a lower level than was ever known before. The inhabitants of the village of 3leilen, on the lake of Zurich, took advantage of this unusual subsidence to reclaim a piece of land from the lake. As the work went on, a learned antiquary, Dr. Ferdinand Keller, discovered the remains of rows of deeply driven piles, and, imbedded in the mud around them, found heaps of rpimitive weapons, tools, and utensils, made of stone and bone. Closer exami nation satisfied him that the piles had supported a platform; that on this platform huts had been raised; and that after being thus occupied, probably for centuries, the structure bad been destroyed by fire. The discovery in the lake of Zurich of these Iceltische pfaltibauten (Celtic pile-buildings), as Dr. Keller called them—habitations lacuere8 (lake dwellings), as other Swiss archteologists have termed them—was followed almost imme diately by the discovery of erections of the same kind in other lakes of Switzerland. No fewer than from 30 to 40 have been found in the upper and lower lakes of Constance; as many as 30 in the lake of Geneva; more than 20 in the lake of Neuchatel; 10 in the lake of Bienne; besides others in the deep peat-bogs which surround the hill of Chamblon, in the Vallee de l'Orbe, and in the lakes of 3Iorat, Inkwyl near Soleure, Moosseedorf near Bern, Phiflikon near Zurich, Wauwyl near Lucerne, and Nussbaumen in the can ton of Thurgau. The site chosen for these lake-dwellings was generally a sunny and bay, with agently shelving bottom of mud or clay. The piles, from 4 to 10 in. in diameter, were rudely fashioned of whatever wood was at band, oak, fir, ash, beech, birch, cherry, or apple. They were driven in a depth of not less than 6 or 7 ft. of water, at a distance of from 100 to 300 ft. from the shore. They were ranged generally from 1 to 2 ft. apart, in the form of a narrow parallelogram, having its longest side in a line with the edme of the lake. At Wangen, on the lake of Constance, the piles, from 30.000 to 40,000 in number, extend about 700 paces in length, and about 120 in breadth,. At .3Iorges, on the lake of Geneva, the piles stretch 1200 ft. in length by 120 ft. in width, so that they would have supported a platform with an area of about 18,000 ft., sufficiently capacious, according to the calculations of M. Frederic Troyon of Lausanne, to contain 316 huts, with a population of 1264 persons. The huts, it would seem, were for the most part circular in shape, measuring from 10 to 15 ft. in diameter; they were of wattles, plastered with clay, masses of which hardened by fire, still bearing the marks of the wattles which it had received when wet and soft, have been recovered from the beds of the lakes. In at least one instance, the remains of a bridge or gang way, leading from the platform to the shore, have been discovered. Many small boats, hollowed out of the trunks of trees, have been found; and one large vessel of the same kind, 50 ft. long, and 3 ft. wide, has been observed at the bottom of the lake of Bienne.