j making the conclusion of your recent 

 contributor correct. But a case wherein 

 — the writer of the confounding article 

 1 would be correct can be easily imagined. 

 If the ship were of the old wooden type 

 I and had a cargo of low density bulk, such 

 as cork, an average density of say 1.0276 

 would be probable. If then this ship 

 were to sink In water of a depth of, say, 

 25,000 feet, it would stop sinking and 

 float at about 6000 feet, provided in sink- 

 ing It lost none of Its cargo; then it could 

 be can-led hither or thither by deep 

 ocean currents. However, an occur- 

 rence of these circumstances Is sufficient- 

 ly rare to hardly Justify the article o< i 

 March 10. A very slight Increase In [j 

 average density (say 1.028), would cause 

 It to float much deeper (12,000 feet). 



An interesting consideration of sinking 

 craft is what happens to a sinking sub- 

 marine which has lost the means of ris- 

 ing to the surface. When Jt has reached 

 6000 feet, the force on evet-y square inch 

 of its surface is 1.2 tons: If it reaches 

 30,000 feet, this force on every square 

 inch Increases to six tons. If the resist- 

 ance of the shell is such that It cannot 

 stand this pressure, the submarine will 

 bo crushed before reaching bottom. T be- 

 lieve this could be demonstrated by 

 watching a fresh egg — a bad one will not 

 sink — go down a long glass tube filled 

 with water; if the column be high enough , 

 —say about ten or fifteen feet — the egg 

 will be cracked before reaching bottom, 

 thus paralleling tho case of a sinking 

 submarine. Of course if a submarine Is 

 flooded, it will sink rapidly to the bottom, 

 no matter how deep, for then It would 

 be like dropping a piece of steel In water. 



The writer Is glad to say that it Is rare 

 indeed that one finds In the columns of 

 the Transcript articles which violate 

 well-established laws of science: and even 

 if there was a slip In the article on a 

 sinking ship, the remarkable accuracy 

 with which it gave its readers the pro- 

 ceedings of the American Academy for 

 the Advancement of Science recently, I 

 outbalances this slip ten times over. | 

 Frank E. La Catisja | 

 , Cambridge, March 18. 



