GUN RECOIL SPRINGS. 151 



TARPAULIN HATS. 



Are best made of vellum or vegetable leather. They are 

 much lighter, and much more durable than those made of painted 

 canvas, but whether they will be adopted by Jack instead of the 

 article made by himself, during his leisure moments, is a matter 

 of doubt. 



DECK SCRUBS, 



Or what are termed by sailors Squeal Gees, are made of a 

 plate of caoutchouc packing, such as is used for engine packing, 

 or of gum-elastic sponge. This article has already been made by 

 one of the licensees* to considerable extent, and has been found 

 to answer the purpose for which it is used, completely. See 

 plate vi., fig. 7. 



GUN RECOIL SPRINGS. 



The strain and injury done to vessels of war by the recoil of 

 the guns, is an evil for which a remedy has long been sought. 

 For this purpose it has been proposed to use springs of gum- 

 elastic, acting either by extension or by compression : in either 

 case, various methods may be suggested for applying them to 

 the gun carriage. See plate , fig. 



• Mr. John Greacen, 98 Broadway, New York. 



