276

MOTIVE POWER EMPLOYED

which is considerably below the proper ex-tent, and will account for the great waste ofcoals.

1 shall now attempt to shew the performanceof the loco-motive engines, with respect to theconveyance of goods upon Rail-roads, andshall confine myself to their application uponthe edge-rail. Taking Experiment XXXIII.as the datum, which, as it was performed in thepresence of several eminent engineers, andwith a view of ascertaining their perform-ance with respect to the rate at which they cantravel in their present state, will be a propermeasure of their utility.

The engine, in that experiment, was sub-jected to a load of 975 cwt., exclusive of theweight of the engine and convoy-carriage; ona mean of the whole number of journeys, theaverage rate was 6.6 miles an hour. I shallcall it 6 miles an hour, for the sake of evenrmmbors. The load was 975 cwt., but, as inthe case of carriages moved along Rail-roads,by self-acting planes, we found that the rela-tive resistance in the most favorable and themost unfavorable weather was as 4:3, weought, perhaps, to apply the same rule to theperformance of the loco-motive engine. In thecase of horses we also found, that in five months