Trevorrick decided to scrap them. He had no intention of driving R 81 under the water. In the event of danger he could submerge and "lie doggo" until he deemed it prudent to break surface. Thus, he cut out an important item in the running costs.
Meanwhile, the roar of the oxygen-acetylene plant had given place to the rattle of riveting-hammers and drilling-machines. All hands worked with a zest, prompted by the hope that they were participators in a profit-sharing scheme. To guard against intruders, watchmen were posted by night, while a boom of timber was stretched across the mouth of Polkyll Creek, to which a noticeboard was affixed with the intimation that "This Creek is temporarily closed to Navigation. Dangerous. By Order."
By whose order it was not stated. Few craft other than pleasure skiffs ever penetrated the secluded backwater, and the season was too late for picnic parties. Some of the local fishermen were "up against" the infringement of their rights, but a judicious expenditure on beer quickly removed their opposition to the temporary closing of the creek.
Quickly the task of disguising the submarine as a tramp steamer progressed. Vertical girders bolted to her bulging sides formed the framework for the side-plating. She was given a raised fo'c'sle and poop; while amidships, by an ingenious arrangement, was a raised structure that could with little trouble be moved fore and aft. On the structure was the dummy charthouse with a funnel in its wake. Thus, by altering the position of the midship structure, the submarine would present the appearance of a "three island vessel" or one of the coasting type with the funnel well aft. In addition, she was given a pair of stumpy masts with derricks, so arranged to be lowered should occasion arise. Ventilating cowls were fixed to various positions on deck, each with a duplicate base, in order to alter the general appearance. Two boats were carried in davits, each constructed of sheet metal and fitted with valves that enabled them to be easily filled and emptied when the submarine dived or came to the surface as the case might be.
In two months from the time the work was first put in hand, R 81, rechristened Alerte of London, was floated out and moored in the centre of Polkyll Creek. If necessary, her presence could be explained by saying that she was about to take a cargo of scrap metal round to Cardiff.
Even at close distance it would be almost impossible for the most practised eye to discover the fake, unless the observer actually went on board. With her black sides streaked with iron rust, her stumpy masts and buff funnel with a black top, she was like many a hundred tramps that nosed their way coastwise from Thurso to Penzance and from Wick to Falmouth.
To complete the deception, Pengelly, who was a skilful penman, made a fictitious "Certificate of Registry" and other necessary ship's papers. Nor was he content with one of each. Six different sets, each in a different name, were prepared and placed on board.
At an early stage in the proceedings, Pengelly had gone over to Penzance in order to interview and enlist the services of that tough old salt Silas Porthoustoc. At the merest hint that he proposed to run a cargo, the skipper of the lugger's eyes gleamed.
"What be't, maaster?" he inquired. "Spirits, lace, or what not?"
"Neither at present," was the reply. "But something highly contraband."