540 ANNUAL RECORD OF SCIENCE AND INDUSTRY. 



is yet a new thing. The air-brake was, on the whole, recom- 

 mended as beino: the best brake in use. 



ENTANGLEMENT OF A WHALE IN A SUBSIAKINE CABLE. 



The instances of damage to submarine cables, resulting 

 from intentional or accidental agencies of marine animals, are 

 becoming by no means rare. We have lately mentioned the 

 fact of the perforation of a cable and the laying bare of its 

 conducting wire by the tooth of a saw-fish ; but a still more 

 remarkable instance is presented in connection with the cable 

 at Kurrachee. This cable failed suddenly on the 4th of July, 

 and the interruption was found to be about 160 miles ofi", 

 where the cable rose over a very uneven and rocky bottom. 

 A repairing steamer was sent out to that point, and on wind- 

 ing in the cable an unusual resistance was experienced. Aft- 

 er some time the body of an immense Avhale was brought to 

 the surface, two turns of the cable having passed around it 

 immediately above the tail. It is thought that the whale 

 had been endeavorino; to rub its barnacles off aojainst the 

 cable, and in turning quickly had made a kink in the line, 

 which held it fast, and was sufficiently strong to resist its ef- 

 forts at release. The strain on the cable in hauling up the 

 whale had caused it to cut through the body, and the carcass 

 sank to the bottom, the tail being brought up. 



COMPOSITION FOR SIGNAL LIGHTS. 



The following mixtures, affording pure colored lights for sig- 

 nals, have been patented in England: White: 100 parts of 

 chlorate of potash, 10 of sulphide of antimony, 15 of boiled lin- 

 seed-oil. Hed: 50 parts of chlorate of potash, 50 of nitrate of 

 strontia, 5 of charcoal, and enough linseed-oil to give a doughy 

 consistency. Green: 50 parts of chlorate of potash, 50 of ni- 

 trate of baryta, 5 of charcoal, and linseed-oil, as in red. The 

 peculiarity claimed is in the use of linseed-oil, which may be 

 replaced by turpentine or a resin. 13 C, June 1, 1873, V27. 



RECENT EXPERIMENTS ON THE STRENGTH OF STEEL. 



It is now seventeen years since Mr. Bessemer introduced 

 his methods of the manufacture of iron and steel to public 

 attention, through the paper read before the British Associa- 

 tion for the Advancement of Science. The present perfected 



