Page 2 Advertisements Column 5

Pelorus Guardian and Miners' Advocate., Volume 30, Issue 29, 16 April 1918, Page 2

I The cable news has frequently re-' ' ferred to the effectiveness of “depth bombs” in the destruction of the U- [ boats. An American writer, in explaini ing the precise results which follow the explosion under the water of these ' oombs, says that all explosives generate an enormous amount of gas. High explosives generate an extra volume of gas; a cubic inch of water expands into a cubic foot of steam at atmospheric pressure. This is 1728 times the volume of the water. When a depth bomb is exploded under water, the gas causes enormous pressure in all directions. What gives way ? The water between the bomb and the surface is pushed upward, is thrown into the air until tne gas can escape. But if a submarine is nearer to the exploding bombs than the surface, it is the shelTof the boat which has to stand the fearful and sudden pressure. It yields; it may crush like an eggshell, or perhaps the plates start, and the air in the U-boat escapes* wstej ffllg it 4 i* la**