ON THE DEVELOPMENTS OF MECHANICAL ENGUSEERING. 501 



at each operation. Fresh water, therefore, was needed, and the problem 

 then arose how to get it ; and that problem was solved, not by the use of 

 sm^'ace-condensation, but by the employment of re-injectiou ; that is to say, 

 an ordinary injection-condenser being used, the water delivered from the 

 hot well was passed into pipes external to the vessel ; after traversing 

 them it came back into the injection-tank sufhciently cooled to be used 

 again. The boilers were worked by coke fires urged by a fan-blast in 

 their ashpits, but I am not aware that this mode of firing was a needful 

 part of the system. 



Engines 'used for liaihvai/s. — At the British Association Meeting of 

 1831 the Manchester and Liverpool Railway had been opened only 

 about a year. The Stockton and Darlington coal-line, it is true, had 

 carried passengers by steam-power as early as 1825 ; but I think we may 

 look upon the Manchester and Liverpool as being the beginning of the 

 passenger and mercantile railway system of the present day. In 1831 

 the locomotives weighed from eight to ten tons, and the speed was 

 about twenty miles per hour, with a pressure of steam in the boiler of 

 from 40 to 50 lbs. The rails were light, they were jointed in the chairs, 

 which wei'e generally carried on stone blocks, thus affording most excel- 

 lent anvils for the battering to pieces of the ends of the rails, that is to 

 say, for the destruction of the very parts where they were most vulner- 

 able. The engines were not competent to draw heavy trains, and it was 

 a common practice to have at the foot of an incline a shed containing a 

 ' bank engine,' which ran out after the trains as they passed, and pushed 

 them up to the top of the hill. Injectors were then unknown, and donkey- 

 pumps Avere unknown, and therefore, when it was necessary to fill up 

 the boiler, if it had not been properly pumped up before the locomotive 

 came to rest, then the locomotive had to run about the Hne in order to work 

 its feed-pumps. To get over this difficulty, it was occasionally the prac- 

 tice to insert into a line of rails, in a siding, a pair of wheels, with their 

 tops level with those of the rails, so that th'e engine wheels could run upon 

 their rims. Then, the locomotive being fixed, to prevent it from moving 

 off the pair of wheels endways, it was put into revolution, its driving wheels 

 bearing, as already stated, upon the rims of the pair of wheels in the rails, 

 and thus the engine worked its feed-pumps, without interfering (by its 

 needless running up and down the line) with the traffic. It should have 

 been stated that at this time there was no link motion, no practical 

 expansion of the steam, and that even the reversal of the engine had to 

 be effected by working the slides by hand gear, in the manner in use in. 

 marine engines. When the British Association originated, although the 

 Manchester and Liverpool Railway had been opened for a year, there is 

 no doubt that the 300 members who then came to this city, found their 

 way here by the slow process of the stage coach, the loss of which we so 

 much deplore in the summer and in fine weather, but the obligatory use 

 of which we should so much regret in the miserable weather now pre- 

 vailing in these islands. In 1881 we know that railways are everywhere. 

 Steel rails, double the weight of the original iron ones, are used. Wooden 

 sleepers have replaced the stone blocks, and they in their turn Avill pro- 

 bably give way to sleepers of steel. The joints are now made by means 

 of fishplates, and the most vulnerable part of the rail, the end, is no 

 longer laid on an anvil for the purpose of being smashed to pieces, bub 

 the ends of the rails are now almost always over a void, and thereby are 

 not more affected by wear than is any other part of the rail. The speed 



