236 LIGHT SCIENCE FOR LEISURE HOURS. 



able to throw shot across the Straits of Dover ; and in 

 the fulness of their faith in that mythical piece of 

 ordnance, they refused to believe that the skill of 

 modern artillerists was unequal to the construction of 

 cannon even more effective. 



If there are any who still believe in the powers 

 ascribed to the far-famed ( pocket-pistol,' they will find 

 their confidence in modern artillery largely shaken by the 

 announcement that it is considered a great matter that 

 one of Whitworth's cannon should have thrown a shot 

 to a distance of very nearly six and a half miles. Not 

 only is this so, however, but it is well known that no 

 piece of ordnance has ever flung a projectile to so great 

 a distance since first fire-arms were invented ; and it 

 may be safely predicted that men will never be able to 

 construct a cannon which as far as range is concerned 

 will do much better than this one of Mr. Whitworth's. 

 The greatest range which had ever before been ob- 

 tained fell somewhat short of six miles. The 7-inch 

 steel gun contrived by Mr. Lynall Thomas had flung 

 a projectile weighing 175 Ibs. to a distance of 10,075 

 yards ; and, according to General Lefroy's ( Handbook 

 of Artillery,' that was the greatest range ever recorded. 

 But Mr. Whitworth's cannon throws a shot more than 

 1000 yards farther. 



Very few have any idea of the difficulties which 

 oppose themselves to the attainment of a great range 

 in artillery practice. It may seem, at first sight, the 

 simplest possible matter to obtain an increase of 

 range. Let the gun be made but strong enough to 



