" It is now plain, that by the tackle 1, 2, the shears can be let go over as for as necessary, and brought back into the perpendicular ; but to counteract this main guy, and keep all steady, the rope 5, 6, 7, with a small tackle upon it, performs the office of an out-ha•ler guy, fixing to the same ring in the rocks, as that of the main shears had before done. This apparatus enabled the cupola to be hoisted and set on whole without a bruise.
" Plate VII.—Plan and description of the work-yard at MU:ay, with its furniture and utensils.
" Figure 1. The general plan of Mill-flay, the dotted line a b c shows the line of low-water spring tides.
"d e. The channel dug from low water to convey vessels to the head of the jetty f g.
i k 1. The area of the work-yard.
" Since the removal of this work, has been built L the long room.
" A c. The marine barracks.
" D D. New streets of Stonehouse.
" Figure 2. Plan of the work-yard and jetty. A B C D, the line terminating the head of the channel. Now any vessel lying against the two large piles B c, on which a pair of shears being erected, can be unloaded of her cargo of stone, and delivered upon a wheel-carriage; that passing along the jetty to the turn-rail E, the carriage is there turned round till it becomes Ur with the rail-road E F; and passing along it, en ters the work-yard, whose boundary is marked by a G G G.
"At T is another turn-rail, which enables the carriage to go on with its burden ; either in the straight line, or to turn there and go along the rail-road in the middle of the yard, and arriving at any destined point, suppose it is there met by a roll-carriage ; for which, planks being temporarily laid, as at 1, the burden (being transferred on small rollers) will be easily moved thereon to the extremity of the yard side ways ; and thus stones can be deposited, as at K K (shown edgewise upward) upon any point of the area of the yard, and returned by the same means.
"The area bounded by the line a a, and the dotted line L L, is the Portland workshed.
" NI denotes one of the bankers; to which, from the wheel carriage (supposed on the rail-road opposite) strong joists being laid, as shown by the dotted lines, the pieces of stone are brought on small rolls; the bankers having notches sunk therein, to receive the ends of the joists.
" In like manner, the area x o was the shed for the moor stone workers.
"The square area P Q denotes the extent of a roof, sup ported by four posts, covering the platform ; whereof a b represents the platings of rough stone walls ; c d one of its principal floor timbers, 6 by 12 ; these being covered with three-inch planks, and brought to a true level, made a stout floor, upon which the courses were brought together.
" R. The cabin for the foreman of the yard.
" s. A small store-room for tools and iron-work.
" a w. The store-shed for Watchet lime and puzzolana. "v x. The shed for bucking or beating the larger parts of the puzzolana upon w v, the bank with three cast-iron beds upon it.
" Figure 3. Supposed a detached figure, being the ground plan of the turn-rail at T (Figure 2) to an enlarged scale, wherein A B is a dormant circle of wood well supported ; of which c marks the cent•e.pin fixed in the transverse beam : E E being connected studs.
F. Portions of the rails, whereon the wheels move, which are kept in place by the fillets nailed on each side.
" c a. The sleepers for supporting the rails at about a yard's distance middle and middle ; as is also show n near E, in Figure 2.
" Figure 4. The plan of the movable turn-rail, and Figure 5 the relative upright ; showing also the section of the dor mant circle. The three last figures having a mutual refer ence, the same parts are marked with the same letters: and furthermore, in Figure • and 5.
" uu r. The rail part of the turn-rail, correspondent to those parts marked F F, Figure 3, in width and height. The rail parts, ii 1, arc strongly framed upon the cross beam K K. and connected by the pieces L L. The whole being poised, with its burden, upon the pin c, but without absolutely touching the dormant circle A B While turning ; for bearing only upon the flat shoulder of the pin, it turns easily ; but, when it is bringing on, or wheeling off the equilibrium upon the pin being destroyed, the ends, n, i, are then supported upon the dormant circle, and the wheels will move steady.
"Figure 7 shows the plan, and Figure 8 the upright view of the wheel-carriage, to the same scale as that of Fign•es 3, 4, and 5. Also Figure 9, and Figure 10, give the upright views of the roll-carriage in two directions. to the same scale ; which show distinctly the manner of suppurting, the axis of the rolls on iron frames ; and how the iron frames are kept upright by four pair of cross bars.