Goods can be profitably transported by canal at a lower tonnage than by railroads; the speed on the canal (for goods) being, however, but one-fifth of the speed on the railroad.
VI.
Goods are transported on the Liverpool and Manchester railroad at three-pence three farthings per ton per mile, with a profit of about 40 per cent. upon the disbursement, having the competition of a canal between its termini.
VII.
A long railroad can be worked with greater relative economy than a short one.
VIII.
Steam engines work with the greatest efficiency and economy, when the resistance they have to overcome is perfectly uniform and invariable.
IX.
The variation of resistance on railroads depends, first, on acclivities, secondly, on curves.
By curves are meant the changes of direction of the road to the right or to the left. The direction of a railroad cannot be changed suddenly by an angle, but must be effected gradually by a curve. Supposing the curve to be (as it generally is) the arc of a circle, the radius of the curve is the distance of the centre of the circle from the curve. This radius is an important element in the estimate of the road.