"Silly little josser!" exclaimed another of the Berthon's crew as the floe tilted under the dog's weight. It looked as if the animal would slide backwards in spite of her frantic efforts to find a firm foothold. Not until her body was half immersed did the sheet of ice recover itself, only to tilt in the opposite direction and precipitate Flirt into the bitterly cold water. Slipping and floundering, the three men pushed the boat to the edge of the canal, then, heedless of the danger of the sharp edge ripping the canvas hull, they launched her and leapt in. "Give way for all you're worth!" shouted Cassidy, who, in the absence of a rudder, gave the rowers directions by pointing with his hand. Already Flirt was showing signs of exhaustion. Her fore-paws were threshing the water, instead of moving strongly and noiselessly beneath the surface. Her hind-quarters were sinking lower, while her head was thrown well back--sure signs that the task she had undertaken was beyond her power. "Way 'nough!" ordered Cassidy. "Grab her, Bill!" The seaman addressed boated his oar and leant over the gunwale, but, caught by the stiff breeze, the lightly-built craft drifted to leeward, just beyond arm's length of the now-benumbed animal. Before the man could grasp his oar, Flirt disappeared beneath the surface. Without hesitation Cassidy took a header over the pointed stern of the Berthon, to reappear ten seconds later with Flirt firmly held by the scruff of her neck. Willing hands relieved the brave sailor of his burden and helped him into the boat. "Crikey! Ain't it 'orribly parky!" he exclaimed. "'Ere, Bill, give me an oar before I'm frozen stiff." "'Ow about it?" enquired Bill, who, having taken Cassidy's place in the stern-sheets, was devoting his attention to the now torpid dog. "Do the 'Instructions for the Treatment of the Apparently Drowned' hold good for a bloomin' animile? Lumme, what's she got lashed round 'er neck--'er kit in a brown-paper parcel, I believe." "Don't heave it overboard," protested Cassidy, as Bill cut the lashings. "Strike me pink! There's writing on it--'Prisoners in a cellar in this house.--Fordyce'. Hallo! This is news for our skipper. Flirt, old girl, you're a brick!" Flirt, beginning to take a renewed interest in life, feebly wagged her stumpy tail. Perhaps she was rather glad she wasn't one in the literal sense of the word, as a brick would have made a poor show in the waters of the Neva. CHAPTER XXVI A Friend in Need "Well done, Cassidy!" exclaimed Lieutenant-Commander Stockdale when the A.B., with his clothes already stiff with ice, came on board. "Go below--don't waste time--and shift into a dry kit; and tell Jones to serve out a stiff tot to you three men." "Beg pardon, sir," said Cassidy, "but we found this gadget lashed round Flirt's neck--something written on it by Mr. Fordyce."