Page:Polar Exploration - Bruce - 1911.djvu/157

Rh below the surface to quite a considerable distance, until something destroyed the equal balance that held it, when it would rapidly rise to the surface and shoot out endwise far above the water. When this happened the ship had to be handled in such a way as to avoid if possible the severe shock it would sustain from the blow of such a huge piece of ice, weighing many tons and as hard as rock. But even when it was impossible for the ship to escape the blow, it was of vital importance to handle her in such a way that the rudder and propeller were not damaged or carried away by the impact of the ice. This was the first time that deep-sea trawling had been attempted in the ice-pack, and if under ordinary circumstances in the open sea great care, accuracy, and considerable practice are required to carry out the operation successfully, much more so was that the case on the present occasion. The Scotia trawling cable was capable of withstanding a strain of more than nine tons, and on more than one occasion the dynamometer showed a strain of more than six tons. Every thousand fathoms of the trawling cable weighed a ton, and on several occasions the Scotia had as much as 4,000 fathoms, i.e. 4½ miles, of cable paid out. It can be understood, therefore, that the operation was no child's play, and that the 40-horse-power winch, the derrick, the