for containing a stock of provisions, water and fuel, for any length of time, besides stowing two or three tiers of casks of lime, cement, and other necessaries for the use of the work. [Sidenote: Praam-boats, or Stone-lighters.] Continuing the description of the marine part of the establishment, we next notice three new praam-boats, or stone-lighters, built for conveying the building materials to the Bell Rock, from the vessels employed in bringing them from the work-yard at Arbroath. The term Praam-boat is applied to a certain description of Norwegian boats, having their stem and stem rounded after a peculiar fashion. The introduction of this phrase, in the Bell Rock service, was purely accidental, having been applied, by Captain Grindlay, Master of the Trinity-House of Leith, to the first or experimental stone-lighter, from its resemblance to the praams of Norway. Those now alluded to, however, were built of a more rounded form, after the Dutch manner. They measured over all, on deck, about 28 feet by 8 feet 6 inches, and their depth of hold may be stated at 2 feet, for, being built by different carpenters, they were not exactly of the same dimensions. They had a considerable spring or sheer, and were constructed for carrying their cargoes entirely upon deck, which formed a kind of _cockpit_ in the waist, having a high gunwale on each side, and a break, both fore and aft, as will be seen in Plate XI., the first tier of stones seldom reaching above the level of the gunwale. They had, consequently, little or no hold, having only what was sufficient for stowing some pig or cast iron ballast, a few empty casks, with the necessary warps, kedge-anchors, and grappling-irons. [Sidenote: Precautions taken for rendering them water-tight and buoyant.] These lighters were built of uncommonly strong materials, both in their timbers, outward planks, and ceiling or lining, which last was caulked and secured in a manner similar to that described for the Floating-light, so that although the outward skin were damaged, by striking or rubbing on the rock, there would still be an additional defence against sinking. Such, however, was the presentiment of danger attached to the landing-department, that besides the precaution of a water-tight lining, each praam was provided with twelve strong empty casks, which were stowed in the hold, and were sufficient to float and render her buoyant, in case of accident. The praams, therefore, became so many life-boats moored in the neighbourhood of the rock. [Sidenote: Method of mooring the Praam-boats.]