THE CREATORS OF THE AGE OF STEEL, 259 



Whitworth projectiles. Whitworth himself attacked the new problem and in 1877 

 prevailed. He made plates of compressed steel, built in hexagonal, each of 

 which was composed of a series of concentric rings around the central disc. 

 The rings prevented the spreading of a crack beyond the one in which it occur- 

 red. Of this material a target was composed nine inches thick, supported by a 

 wood backing against a sandbank. In front a horizontal iron tube was put to 

 receive the fragments of the shot. Against this target a Pelliser shell, weighing 

 250 pounds, was fired point blank from a nine-inch gun, with fifty pounds of 

 pebble powder, at a distance of thirty yards. This shell would have passed 

 through twelve inches of ordinary armor; against the new target it was shattered 

 into innumerable fragments. The target was drawn back eighteen inches into 

 the sand. The fragments of the projectile escaping at the end of ten tubes con- 

 tinued their rotation in such a manner as to cut through the planks in front of 

 the displaced target. The only piece that survived the shock was a flattened 

 mass of eight pounds, formed from the apex of the shell and left imbedded in 

 the target, where it had made an excavation of eight inches in diameter, and 

 four-tenths of an inch deep in the deepest part. The ring which received the 

 shot was not cracked. 



This experiment alone effected a revolution in naval armament. 



There is not room here to speak of Sir Joseph Whitworth's eminent services 

 to the cause of technical education. He has devoted a large part of the great 

 fortune won by his inventive genius to the founding of schools and scholarships 

 for the benefit of young men desiring to explore the wide field of mechanical 

 industry. 



Sidney Gilchrist Thomas. — It will be remembered that the Bessemer proc- 

 ess failed after its first success, and that the reason of that failure was the pres- 

 ence of phosphorus in the pig iron. Such an insuperable obstacle did this pre- 

 sent that Bessemer gave up the problem and went to Sweden for his pig. To 

 Mr, Sidney Gilchrist Thomas belongs the honor of discovering a means for get- 

 ting rid of this obnoxious element. Acting upon his idea, he and his cousin Mr, 

 Gilchrist, the first twenty-six, the latter twenty- five years old, conducted an ex- 

 haustive series of experiments to find a base with which phosphorus would unite. 

 A base is the name given in chemistry to any element for which an acid has 

 affinity. At last they made bricks of lime and magnesia, which they subjected 

 to an intense white heat, when they became hard as flint. With these bricks, 

 which were a base, they lined their converters, the melted pig iron was poured in 

 and the phosphorus at once left the metal and attached itself to the bricks. A 

 quantity of lime is added to the run, and the result is a thoroughly dephosphor- 

 ized iron. 



The news of the new process spread through Europe, and to show how 

 greatly the invention was appreciated the following circumstance is detailed. A 

 continental iron-master «alled on Mr. Thomas at 7:30 one April morning to ar- 

 range for terms for the use of the patent. Just as they were concluded a tele- 

 gram was handed to Mr. Thomas stating that another iron-master from the sam.e 



