Directions for Working Portable Steam- Engines. 435 



Preparations for Moving the Engine. 



When the day's work is over, and the eng^ine is going to be 

 moved to another place, the water should be run out of the boiler 

 when the steam is quite down ; the practice of blowing all the 

 water out of the boiler directly the fire is dropped is a very bad 

 one, for the sudden contraction of the tubes caused by the rapid 

 cooling makes them leaky, and does much mischief : the boiler 

 should never be refilled when hot ; for the same reason the water 

 should never be left in the boiler when the engine is going to 

 travel over a hard road ; if it is merely going to be moved on soft 

 ground for a short distance, no harm will be done beyond adding 

 greatly to the weight ; care should be taken that the fire-bars do 

 not shake out, and thus be lost, when the engine is travelling. 



Governor Balls. 



It is a good plan to take the levers carrying the balls off when 

 the engine is going to travel, as the jolting on roads is very apt 

 to bi'eak these levers ; they may be carried conveniently in the 

 smoke-box, wrapped up in hay or shavings to prevent injury. 



EoAD Wheels to be occasionally examined. 



Before the engine travels any great distance the road wheels 

 should be taken off, and the axles examined and cleaned. If the 

 axles are much cut they should be dressed over with a smooth file 

 to take off all roughness ; they should be well greased with a 

 mixture of oil and melted tallow before going on a journey ; and 

 if the journey be long, the small screws in the naves of the wheels 

 should be occasionally taken out, and fresh oil be poured into the 

 axle-boxes. 



Cleaning Engine. 



After the day's work is done the engine should be well rubbed 

 over with cotton waste, and all dust and grit should be removed, 

 also all superfluous oil which may have accumulated during 

 working ; the chimney should be lowered down, and the engine 

 be covered over with the tarpauling furnished for that purpose ; the 

 engine should always be carefully covered up when travelling, 

 to prevent the working parts from becoming injured by dust or 

 mud. 



Washing out Boiler. 



The boiler must be well washed out and cleansed after about 

 twelve or fourteen days' working; to do this the brass plugs and 

 mud-doors round the bottom of the outside shell of the fire-box 

 must be taken out ; water must be poured freely into the boiler 

 through the opening where water is poured in, the mud and 

 scales being at the same time loosened and pulled out with a 



