258 KANSAS CITY REVIEW OF SCIENCE. 



in the internal gauge when both are clean and dry, while the smaller. 5 7 69 

 gauge is so loose in it as not to appear to fit at all. These gauges are finished 

 with great care, and are made true after being case-hardened. The effect of 

 applying a drop of fine oil to the surface of this gauge is remarkable. It will be 

 observed that the fit of the larger cylinder becomes more easy, that of the smaller 

 more tight. * * * It is thus obvious to the eye and the touch that 

 the difference between these cylinders of one ten-thousandth of an inch is an 

 appreciable and important quantity, and what is now required is a method which 

 shall express systematically and without confusion a scale applicable to such 

 minute differences of measurement." The Whitworth gauges have been adopted 

 by the Government as standards of measurement. 



The accuracy in mechanical processes rendered possible by Whitworth's in- 

 ventions bore its first fruit in a direction which the inventor little expected. 



England was engaged in the Crimean war, and the Enfield rifle, a hand- 

 made weapon, was the arm of her forces. It became necessary to have these 

 guns in large quantities, and the burning question of the hour was how to make 

 these rifles by machinery. The science of projectiles was then entirely empiric. 

 Some guns shot well and some shot ill, but why these were good and those bad 

 no one knew. Whitworth went before a Parham'entary committee, and told it 

 that until the data of rifling were esiablished good machine-made guns would be 

 impossible. It was necessary to find out what made an effective gun by contin- 

 ued experiment before anything else was done. 



England needed a million rifles. To make these by the processes then in 

 use would have taken Birmingham twenty years. It was agreed that the Govern- 

 ment should bear the expenses of Whitworth's experiments. 



A gallery was set up at Rusholme, 500 yards long, furnished with tissue 

 paper screens in order to track the bullets throughout their flight, and with slid- 

 ing targets. The experiments began in March, 1855. The Enfield rifle had a 

 bore of .577 inch and the rifling had one turn in 78 inches. The first result was 

 that in every particular the Enfield was found to be wrong Whitworth made 

 barrels with one turn in 60 inches, one in 30, one in 20, one in 10, one in 5 and 

 one in i inch. To be brief, he determined conclusively that the best rifle had one 

 turn in twenty inches, a minimum diameter of forty-five inches, and a rounded 

 hexagonal instead of a circular bore. After beating all other guns at short ranges 

 the Whitworth rifle had a deviation of about 4.62 feet at 1,400 yards. The En- 

 field could not hit the target at all. With a steel bullet Whitworth's rifle perfo- 

 rated plates of iron half an inch thick at an obliquity of fifty degrees, and easily 

 passed through thirty four half-inch elm boards. 



Applying the same principles to artillery, Whitworth devised a gun which 

 threw two and one-fourth hundred weight of iron six and a half miles. 



To such a great superiority did he bring artillery, first by his invention of 

 compressed steel, next by making the guns breech-loading, and finally by increas- 

 ing the size of the powder chamber, that it began seriously to be doubted whether 

 any armor could be made able to resist the crushing force of the square-headed 



