1911] on Travt'lUiig at High Speeds on Surface of Earth. 131 



released causes the train to stop, the train independently stops itself 

 npon coming to a portion of the line not cleared by the previous train. 



I have given you some examples that this country is not so far 

 behind as we are so often told ; and we have another in the fact that 

 the District Railway has created a most beautiful system, by which 

 the signalman is now absolutely independent of fog or darkness ; he 

 can see every train, or rather its picture, as it moves along the track 

 in an illuminated diagram in front of him. No one could watch, as 

 I have had the privilege of doing, the operation of this system in a 

 signal-bos without feeling certain that it must become universal in a 

 very short time. You may like to see an actual panel from a signal- 

 box and a view of what the interior is like with the signalman ope- 

 rating, instead of cumbrous levers, only a few small handles. 



With regard to the question of vibration and oscillation, these are 

 gradually being diminished as machinery is perfected, and you will 

 see from the model illustration that they are important, and may 

 become very serious. They have for instance, given Mr. Brennan 

 much trouble in perfecting his wonderful mono-rail, with which we 

 shall yet perhaps see every record ]:»roken ; and you will remember 

 Mr, Parsons' statement in this hall a week or two ago that an ounce 

 out of balance on the Laval turbine represents an actual pull at the 

 axle of no less than a ton. 



There are many other features which I have not time to enter 

 into. There is one, however, which I will briefly touch upon, as it 

 is the secret of our safe railway travelHng. I will illustrate the 

 matter by an experiment in which a pair of wheels connected by an 

 axle keyed firmly to both are made to run along a pair of rails. You 

 will notice that the wheels are " coned " instead of having cylindrical 

 rims, and it is easy to see that any movement sideways is at once 

 corrected automatically, and within certain limits no rim at all is 

 required for the flanges in order to keep the wheels upon the rails. 

 The same model illustrates the important property of " super-eleva- 

 tion " applied to the outer rail of a curve. You will see, with proper 

 super-elevation, the wheels run safely round this sharp curve even at 

 a high speed. Time does not permit me to enter at any length on 

 the question of development of power or the nature of resistance to 

 motion. I will content myself with saying that, with regard to the 

 former, we have already seen that the power of flight has been made 

 possible by the invention of the small high-power internal-combustion 

 engine, and it is to the same invention that the marvellous speeds 

 obtained with small boats is due. We can scarcely realise what will 

 be the result when the internal-combustion engine has been developed 

 further for the purpose of locomotion. Our prospects of a further 

 great advance in speed record-breaking appears to lie in this direction, 

 and we already hear of a new car of 250 horse-power with which a 

 speed of 140 miles per hour is confidently expected. 



On water, as on land, our actual speed of travelling falls far below 



K 2 



