Masterpieces of Science 



ployed in working the railway, George Stephen- 

 son was in constant communication with his son 

 Robert, who made frequent visits to Liverpool 

 for the purpose of assisting his father in the 

 preparation of his reports to the board on the 

 subject. Mr. Swanwick remembers the vivid in- 

 terest of the evening discussions which then took 

 place between father and son as to the best mode 

 of increasing the powers and perfecting the 

 mechanism of the locomotive. He wondered 

 at their quick perception and rapid judgment on 

 each other's suggestions; at the mechanical diffi- 

 culties which they anticipated and provided for 

 in the practical arrangement of the machine ; and 

 he speaks of these evenings as most interesting 

 displays of two actively ingenious and able minds 

 stimulating each other to feats of mechanical 

 invention, by which it was ordained that the 

 locomotive engine should become what it now is. 

 These discussions became more frequent, and 

 still more interesting, after the public prize had 

 been offered for the best locomotive by the 

 directors of the railway, and the working plans 

 of the engine which they proposed to construct 

 had to be settled. 



One of the most important considerations in 

 the new engine was the arrangement of the boiler, 

 and the extension of its heating surface to enable 

 steam enough to be raised rapidly and continu- 

 ously for the purpose of maintaining high rates of 

 speed the effect of high pressure engines being 

 ascertained to depend mainly upon the quantity 

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