284 LIGHT SCIENCE FOR LEISURE HOURS. 



a sword-fish. No instance had ever been recorded in 

 which a sword-fish had been able to withdraw his 

 sword after attacking a ship. A defence was founded 

 on the possibility that the hole had been made in some 

 other way. Professor Owen and Mr. Frank Buckland 

 gave their evidence ; but neither of them could state 

 quite positively whether a sword-fish which had passed 

 its beak through three inches of stout planking could 

 withdraw without the loss of its sword. Mr. Buckland 

 said that fish have no power of "backing," and ex- 

 pressed his belief that he could hold a sword-fish by the 

 beak ; but then he admitted that the fish had consider- 

 able lateral power, and might so " wriggle its sword 

 out of a hole." And so the insurance company will 

 have to pay nearly six hundred pounds because an ill- 

 tempered fish objected to be hooked, and took its 

 revenge by running full tilt against copper-sheathing 

 and oak-planking. 



(From the Daily News, December 11, 1868.) 



THE SAFETY-LAMP. 



As the late colliery explosions have attracted a 

 considerable amount of attention to the principle of 

 the safety-lamp, and questions have arisen respect- 

 ing the extent of the immunity which the action 

 of this lamp secures to the miner, it may be well 



