Already the _Calder’s_ crew had taken steps to assist the salvage people in the task of floating the prize. The hatchways, with the exception of that of the conning-tower, had been hermetically closed, and the watertight doors in the for’ard bulkhead shut and shored up to withstand the pressure of water in the holed fore-peak.
By the time the lighters were made fast, one on either side of the submarine, the level of the water was up to within fifteen inches of the conning-tower hatchway. Quickly hoses, connected to Downton pumps, were led from the lighters to the water-ballast tanks of the submarine, since it had been found impossible to "start" the ballast by means of hand pumps.
It was a race against time and tide. The mechanical appliances won, and soon the _Calder’s_ officers and crew had the satisfaction of seeing the submarine’s deck appear close to the surface.
She still had a pronounced "dip", the flooded for’ard compartment tending to depress her bow; but, supported by the two lighters, she was prevented from sinking. Then, taken in tow by the tug, the prize, with her cumbersome attendants, waddled slowly for Harwich.
Her part in this supplementary business ended, the _Calder_ slipped off at full speed to the position where the _Dimpled Lassie_ and the _Carse o’ Gowrie_ still held a resolute grip on the recovered cable.
As Skipper M’Kie had surmised, neither of the trawlers had been molested by the German battle-cruisers or destroyers. Carried away by their frantic desire to make a display of frightfulness upon an unprotected English watering-place they had totally ignored the seemingly innocuous cable-grappling craft.
"It will blow like billy-oh before morning," remarked Lieutenant Crosthwaite to his subordinate. "I’m going to tell them to buoy and slip the cable. We’ve done very well, I think. You might make an observation; I’ll take another, and we’ll check our calculations. I’ll guarantee we won’t have much trouble in fishing up the cable next time."
Crosthwaite’s orders to the skippers of the trawlers were smartly carried out, and the cable, left with its position marked by a green wreck-buoy, a sufficient guarantee against detrimental examination by curious fishermen. Before sunset the _Calder_ and her two charges were snug in Lowestoft harbour, the crews being cautioned against the risk of letting fall any hint concerning their recent work--an injunction that they loyally carried out.