SKIMMING THE SURFACE 



of impact was at least sixty miles an hour. There are 

 instances of such powerful penetration that the sword of 

 the fish has been forced through twenty inches or more 

 of hard wood sheathed with copper. Such instances 

 clearly indicate an enormous speed at the moment of 

 impact, so that (considering the nature of the "sword" 

 and the depths of penetration) sixty miles an hour is 

 evidently no exaggeration. 



The shape of the sail-fish's body is admirably adapted 

 for its high-speed, torpedo-like actions. Its sword is not 

 as long as that of the true swordfish, but the fish itself 

 reaches a total length of over six feet, has a stream-Hned 

 flexible body, sloping back to its great deeply-forked tail : 

 a body covered with elongated ''scutes", or horny plates. 

 The huge dorsal fin, deeply notched, simulates the 

 appearance of a ship under sail as it appears above the 

 water. 



Swordfish may be classified among surface creatures of 

 the sea, and only the fact that its occasional leaps into the 

 air are not prolonged into ghding flights (for which it is 

 not naturally adapted) prevents some of its species from 

 challenging the flying-fish's above-water record. But the 

 sail-fish's under-water record of seventy miles an hour 

 (vouched for by unimpeachable authorities) makes the 

 flying-fish's over-water record of fifty miles an hour seem 

 insignificant, when the resistances of the media are com- 

 pared. To fully appreciate the underwater speed of the 

 sail-fish, and the extraordinary efficiency of its stream- 

 Hned structure, one should compare the speeds attainable 

 by man's inventions : the submarine and the aeroplane. 

 Seventy miles per hour would be an extraordinary speed 

 for a submarine — ^yet the sail-fish is not a mechanism but 

 a living creature. 



Whatever creatures may be found on the ocean floors 

 — or may remain to be discovered — one cannot imagine 

 that any will be more fantastic than those we are now 

 examining on the surface of the world's seas — yet space 



41 B* 



