Somewhat Statistical.  
It has been already said that the Bell Rock rises only a few feet out of the sea at low tide. The foundation of the tower, sunk into the solid rock, was just three feet three inches above low water of the lowest spring-tides, so that the lighthouse may be said with propriety to be founded beneath the waves.
 
One great point that had to be determined at the commencement of the operations was the best method of landing the stones of the building, this being a delicate and difficult process, in consequence of the weight of the stones and their brittle nature, especially in those parts which were worked to a delicate edge or formed into angular points. As the loss of a single stone, too, would stop the progress of the work until another should be prepared at the workyard in Arbroath and sent off to the rock, it may easily be imagined that this matter of the landing was of the utmost importance, and that much consultation was held in regard to it.
 
It would seem that engineers, as well as doctors, are apt to differ. Some suggested that each particular stone should be floated to the rock, with a cork buoy attached to it; while others proposed an air-tank, instead of the cork buoy. Others, again, proposed to sail over the rock at high water in a flat-bottomed vessel, and drop the stones one after another when over the spot they were intended to occupy. A few, still more eccentric and daring in their views, suggested that a huge cofferdam or vessel should be built on shore, and as much of the lighthouse built in this as would suffice to raise the building above the level of the highest tides; that then it should be floated off to its station on the rock, which should be previously prepared for its reception; that the cofferdam should be scuttled, and the ponderous mass of masonry, weighing perhaps 1000 tons, allowed to sink at once into its place!
 
All these plans, however, were rejected by Mr Stevenson, who resolved to carry the stones to the rock in boats constructed for the purpose. These were named praam boats. The stones were therefore cut in conformity with exactly measured moulds in the workyard at Arbroath, and conveyed thence in the sloops already mentioned to the rock, where the vessels were anchored at a distance sufficient to enable them to clear it in case of drifting. The cargoes were then unloaded at the moorings, and laid on the decks of the praam boats, which conveyed them to the rock, where they were laid on small trucks, run along the temporary rails, to their positions, and built in at once.
 
Each stone of this building was treated with as much care and solicitude as if it were a living creature. After being carefully cut and curiously formed, and conveyed to the neighbourhood of the rock, it was hoisted out of the hold and laid on the vessel’s deck, when it was handed over to the landing-master, whose duty it became to transfer it, by means of a combination of ropes and blocks, to the deck of the praam boat, and then deliver it at the rock.
 
As the sea was seldom calm during the building operations, and frequently in a state of great agitation, lowering the stones on the decks of the praam boats was a difficult matter.
 
In the act of working the apparatus, one man was placed at each of the guy-tackles. This man assisted also at the purchase-tackles for raising the stones; and one of the ablest and most active of the crew was appointed to hold on the end of the fall-tackle, which often required all his strength and his utmost agility in letting go, for the purpose of lowering the stone at the instant the word “lower” was given. In a rolling sea, much depended on the promptitude with which this part of the operation was performed. For the purpose of securing this, the man who held the tackle placed himself before the mast in a sitting, more frequently in a lying posture, with his feet stretched under the winch and abutting against the mast, as by this means he was enabled to exert his greatest strength.
 
The signal being given in the hold that the tackle was hooked to the stone and all ready, every man took his post, the stone was carefully, we might almost say tenderly, raised, and gradually got into position over the praam boat; the right moment was intently watched, and the word “lower” given sternly and sharply. The order was obeyed with exact promptitude, and the stone rested on the deck of the praam boat. Six blocks of granite having been thus placed on the boat’s deck, she was rowed to a buoy, and moored near the rock until the proper time of the tide for taking her into one of the landing creeks.
 
We are thus particular in describing the details of this part of the work, in order that the reader may be enabled to form a correct estimate of what may be termed the minor difficulties of the undertaking.
 
The same care was bestowed upon the landing of every stone of the building; and it is worthy of record, that notwithstanding the difficulty of this process in such peculiar circumstances, not a single stone was lost, or even seriously damaged, during the whole course of the erection of the tower, which occupied four years in building, or rather, we should say, four seasons, for no work was or could be done during winter.
 
A description of the first entire course of the lower part of the tower, which was built solid, will be sufficient to give an idea of the general nature of the whole work.
 
This course or layer consisted of 123 blocks of stone, those in the interior being sandstone, while the outer casing was of granite. Each stone was fastened to its neighbour above, below, and around by means of dovetails, joggles, oaken trenails, and mortar. Each course was thus built from its centre to its circumference, and as all the courses from the foundation to a height of thirty feet were built in this way, the tower, up to that height, became a mass of solid stone, as strong and immovable as the Bell Rock itself. Above this, or thirty feet from the foundation, the entrance-door was placed, and the hollow part of the tower began.
 
Thus much, then, as to the tower itself, the upper part of which will be found described in a future chapter. In regard to the subsidiary works, the erection of the beacon house was in itself a work of considerable difficulty, requiring no common effort of engineering skill. The principal beams of this having been towed to the rock by the Smeaton, all the stanchions and other material for setting them up were landed, and the workmen set about erecting them as quickly as possible, for if a single day of bad weather should occur before the necessary fixtures could be made, the whole apparatus would be infallibly swept away.
 
The operation being, perhaps, the most important of the season, and one requiring to be done with the utmost expedition, all hands were, on the day in which its erection was begun, gathered on the rock, besides ten additional men engaged for the purpose, and as many of the seamen from the Pharos and other vessels as could be spared. They amounted altogether to fifty-two in number.
 
About half-past eight o’clock in the morning a derrick, or mast, thirty feet high, was erected, and properly supported with guy-ropes for suspending the block ............