Page:Walker - An Unsinkable Titanic (1912).djvu/127

AN UNSINKABLE TITANIC ample for safety. Her fragility and vulnerability lie in the fact that her framework is overlaid with a relatively thin skin of plating, an inch or so in thickness, which, while amply strong to resist the inward pressure of the water, the impact of the seas, and the tensile and compressive stresses due to the motion of the ship in a seaway, etc., is readily fractured by the blow of a collision.

In a previous chapter it was shown that when the Titanic is being driven at a speed of 21 knots, she represents an energy of over 1,000,000 foot-tons. If this enormous energy is arrested, or sought to be arrested, by some rigid obstruction, whether another ship, a rock, or an iceberg, the delicate outside skin will be torn like a sheet of paper.

It was shown in Chapter IV that protection against flooding of a ship through damage below the water-line is obtained by subdividing the hull into separate watertight compartments, and that, roughly speaking, the degree of protection is proportionate to the extent to which this subdivision is carried. Applying this to the Titanic, we find that she was divided by 15 transverse bulkheads into 16 separate compart- [ 105 ]