The stone to be set being hung in the tackle, and its bed of mortar spread, was then lowered into its place, beaten with a heavy wooden mall, and levelled with a spirit-level; and the stone being accurately brought to its marks, was considered as set in its proper position. The next thing was to keep it there, notwithstanding the utmost violence of the sea might beat upon it before the mortar was thoroughly hard and dry. Therefore the carpenter dropped into a couple of vertical grooves, which had been previously cut in "the waist" of the stone, each an inch deep and three inches wide, two oaken wedges, one upon its head, the other with its point downwards, so that the two in each groove would lie heads and points. [Illustration: Foundation wedges.] With an iron bar, about two inches and a half broad, a quarter of an inch thick, and two feet and a half long, he then drove down one wedge upon the other--very gently at first, so that the opposite pairs of wedges, being equally tightened, would equally resist each other, and the stone would therefore keep its place. In like manner, a couple of wedges were pitched at the top of each groove; the dormant wedge (_i.e._, the one with the point upward) being held in the hand, while the drift wedge (i.e., the one with the point downward) was driven with a hammer. So much as remained above the upper surface of the stone was cut away with saw or chisel; and, generally, a couple of thin wedges were driven very moderately at the butt-end of the stone, whose tendency being to force it out of its dove-tail, they would, by moderate driving, assist in preserving the steadiness of the entire mass, in opposition to any violent agitation arising from the sea. [Sidenote: Progress of the work.] The stone thus firmly secured, a certain portion of mortar was liquefied, and the joints having been carefully "pointed," this liquid cement was poured in with iron ladles, so as to occupy every vacant space. The heavier part of the cement naturally fell to the bottom, while the fluid was absorbed by the stone. The vacancy thus left at the top was repeatedly refilled, until all remained solid; then the top was pointed, and, where necessary, defended by a layer of plaster. The whole of the foundation having thus been brought to a proper level, some other means were required to secure a similar degree of solidity for the superstructure. A hole, one foot square, was accordingly cut right through the middle of the central stone in the sixth course; and at equal distances in the circumference were sunk eight other sockets, each one foot square, and six inches deep. A strong plug of hard marble, also one foot square, but twenty-two inches long, was driven into the aforementioned central cavity, and set fast with mortar and wedges. This course, however, was only thirteen inches in depth; consequently the marble plug rose nine inches above the surface.