58 Mr Russell on the Fallacies of the 



Now, it has been proposed for Steam Navigation, but to this 

 it is peculiarly inapplicable. In a steam-vessel, it is useful to 

 have the axis of rotation as fiigh and the weight of the engine as 

 loza as possible. Now, if the engine be placed on this axis, as it 

 would be in the case of the rotatory engine, one of two evils would 

 follow; the axis would either require to be much lowei-ed, or the 

 weight of the engine would be so high as to make the vessel the 

 very reverse of steady. By such a disposition of its parts it must 

 necessarily be rendered crank, and have its power greatly di- 

 minished. In the present engine, the weight is immediately above 

 the floor of the vessel, and the axis in contact with the deck. 



Applied directly to the axis of a Steam-Carriage or Locomotive 

 Engine, there are insuperable objections to the rotatory engine. 

 As there would be no spring between it and the wheels, every 

 jolt would derange the machinery. The weight of the engine, 

 rigidly connected to the axle, would reciprocate the evil, and 

 knock the wheels to pieces. These evils ai"e prevented in the 

 reciprocating engine, by the detachment of the engine from the 

 axle, and tlie propagation of power through rods, wheels, or 

 chains, to the propelling wheel or axis. It is indeed a radical 

 defect in some of the existing forms of the locomotive engine, 

 that the detachment is less perfect than might be desired. This 

 very adjustment, so impracticable with the rotatory engine, was, 

 even with the superior facilities presented by the form of recip- 

 rocating locomotion, one of the greatest impediments to the 

 success of elemental locomotion. 



VI. In addition to the above-mentioned advantages possessed 

 by the reciprocating engine above the rotatory one, it presents 

 facilities (altogether wanting to the latter) for working directly 

 the subordinate appendages of the steam-engine, such as cold- 

 water pump, its own feeding pump, &c. If the engine be a 

 condenser, the simplicity of the reciprocating mechanism of the 

 air-pump puts the rotatory engine altogether hors de combat. 



VII. All these considerations, of the most important practical 

 bearing, demonstrate clearly to us, that if there be no very con- 

 siderable loss of power in the reciprocating engine, we have 

 little inducement to make the substitute of the rotatory chamber 

 and revolving piston for the cylinder and reciprocating piston. 



It appears, on the contrary, both from theory and the practical 

 working of the steam-engine of ordinary construction, that, with 



