Before the Rosalie was abreast of the buoy the Scoutmaster's forecast proved to be correct. Insidiously the white, dank mist swept down, until the bold outlines of Christchurch Head were blotted out. Then the fog thickened until the range of visibility was limited to about twenty yards.
"We're all right so far," said Mr. Armitage cheerfully. "Out of the way of Channel traffic, and, even if the fog doesn't lift, we'll pick up the entrance to Poole Harbour by taking soundings. Plenty of time for that, however. Keep her on West by 1/2 South for the present, Peter. Warkworth and Woodleigh, get your oilskins on and go for'ard. Keep a sharp look-out, especially for lobster lines. There are a lot off this ledge."
"What would happen if we struck one?" asked Flemming.
"It might get round our props and stop both motors," replied the Scoutmaster. "But I'm looking at it from a fisherman's point of view. Lobster pots cost money, and take a lot of labour to bring out and place in position, and no one but an incompetent navigator or a malicious individual would deliberately cut away the lobster-pot lines. I think we'll slow down to five knots, Roche. It will give us a better chance if there are any fishing-boats in the bay."
Mr. Armitage glanced at his watch. Working by "dead reckoning", he knew that even with the west-going tide an hour would elapse before the Rosalie approached the dangerous Hook Sands off the entrance to Poole Harbour.
"Weird sort of business, eh, Peter?" remarked Roche, joining his chum in the wheel-house.
Stratton nodded, and peered into the compass-bowl. The windows of the wheel-house were wide open, and the dank mist settled on the glass of the binnacle so that the helmsman had to be constantly wiping it to be able to observe the compass-card.
"All in a day's work, I suppose," he replied. "This is the thickest fog we've struck. I don't think I'd care about it if I were on my own bat," he confided; "but Mr. Armitage knows this part, so that's all right."
Mr. Armitage, although he did not overhear the remark, was less sanguine. Part of his time in the R.N.V.R. had been spent at Poole in the M.-L. flotilla, and he had seen the bar under almost every possible condition, from the flat calm of a perfect August day to the shrieking, howling, south-easterly gale of mid-December. He had a wholesome respect for Poole Bar, and, with fog limiting the range of vision to a few yards, he realized that an error of judgment might result in the Rosalie ending her career either upon the dangerous Hook Sands or on the surf-swept shoals of Studland Bay.
Half an hour after the Rosalie passed Christchurch Head a breeze sprang up from the south-east—a breeze that speedily developed into a hard blow.