Injuries arising from;  Fast coach; Heavy waggon
Atmospheric changes         20         20
Wheels                      20         35.5
Horses’ feet drawing        60         44.5
Total injury               100        100

Supposing it, therefore, to be ascertained that the wheels of steam carriages do no more injury to roads than other carriages of equal weight travelling with the same velocity, the committee now possessed the means of approximating to a just rate of toll for steam carriages.(1*)

302.  As connected with this subject, and as affording most valuable information upon points in which, previous to experiment, widely different opinions have been entertained; the following extract is inserted from Mr Telford’s Report on the State of the Holyhead and Liverpool Roads.  The instrument employed for the comparison was invented by Mr Macneill; and the road between London and Shrewsbury was selected for the place of experiment.

The general results, when a waggon weighing 21 cwt was used on different sorts of roads, are as follows: 

lbs 1.  On well-made pavement, the draught is 33

2.  On a broken stone surface, or old flint road 65

3.  On a gravel road 147

4.  On a broken stone road, upon a rough pavement foundation 46

5.  On a broken stone surface, upon a bottoming of concrete, formed of Parker’s cement and gravel 46

The following statement relates to the force required to draw a coach weighing 18 cwt. exclusive of seven passengers, up roads of various inclinations: 

Inclination; Force required at six miles per hour; Force at eight miles per hour; Force at ten miles per hour

lbs     lbs     lbs
1 in  20   268     296     318
1 in  26   213     219     225
1 in  30   165     196     200
1 in  40   160     166     172
1 in 600   111     120     128

303.  In establishing a new manufactory, the time in which the goods produced can be brought to market and the returns be realized, should be thoroughly considered, as well as the time the new article will take to supersede those already in use.  If it is destroyed in using, the new produce will be much more easily introduced.  Steel pens readily took the place of quills; and a new form of pen would, if it possessed any advantage, as easily supersede the present one.  A new lock, however secure, and however cheap, would not so readily make its way.  If less expensive than the old, it would be employed in new work:  but old locks would rarely be removed to make way for it; and even if perfectly secure, its advance would be slow.