Conglomerate or pudding-stone has often a picturesque outline in its decay, more especially if its included fragments have a considerable range of size. Large tracts Of this rock exist in various parts of Britain, particularly in Scotland, where the basement beds of the Old Red Sandstone consist of a coarse conglomerate, sometimes several thousand feet in thickness. Such enormous masses form the scenery of a large part of East Lothian, and are found in detached patches across into Peeblesshire and Lanark. In the north, too, the neighbourhood of Inverness and other parts of the same district display conspicuous conglomerate hills. Unless where laid bare by streams or by the action of breakers, the contour of these hills is rounded and tame, with a scanty covering of short scrubby grass and very few protruding bosses of rock. But where a mountain torrent has cut its way down the hill side, the ravine thus formed exhibits broken walls and pillars of rock made up of rounded balls of every shade and size, cemented by a dark-red or green paste. The cementing material is sometimes clay, sometimes lime, and its variable nature gives rise to a corresponding inequality in the amount and form of decomposition. Where the rounded pebbles are bound together by clay, rains act with rapidity in washing away the cement, and the component balls fall out by degrees, leaving a cliff strangely roughened by protruding knobs, and eaten away into clefts and hollows. When the pebbles are held in a crystallized matrix of lime, they usually remain longer together, and may sometimes be seen standing up in the form of detached rugged pillars that defy all regularity of size or outline, and remind one of a sort of rude grotto-work. Such irregularities become still more marked where to the action of the rains there has been added the spray of the ocean. A coast-line of conglomerate, where the rock rises into cliffs, is always a romantic one; caves, pillars, and ruined walls, all in the same rough grotto style, meet us at every step. Here, too, we can mark the varying effect of the waves upon the lower portions of the rock, eating it into cavernous holes and leaving rugged projecting pinnacles to which the mottled colours of the included pebbles give an additional and peculiar effect.