transport and the demand for it depends what it is worth while to give for carrying an article from A to B. Obviously the demand will be affected by the nature of the merchandise. If it be of a costly nature, such as manufactured articles, producers of it or dealers in it can afford to pay a higher rate than if it were of low value; a rate of 3d. a ton per mile, which might be prohibitive of the carriage of sand or lime, would add to the value of silk or velvet only an insignificant percentage.[31] [30] In the Report made by M. Richard Waddington in the name of the Commission of the Third System of Railway Tariffs, special or differential rates are thus referred to. “These Tariffs are established in compliance with a trade demand which varies, as one can easily understand, according to the locality and district concerned. Like intelligent merchants the administrators of the railway companies have based their rate of charges on the law of _Supply and Demand_....” The celebrated expression of M. Solacroup, director of the _Orleans Company_, sums up the considerations which led to the compilation of special tariffs. “_In the matter of Transport Tariffs there is only one rational rule, viz., to ask of merchandise all it can pay; any other principle is no principle._” [31] It may be objected that under such a system companies might extort exorbitant sums from traders who must send their goods. But (1) the figures and returns referred to later on show that in fact the companies have not made such charges, but have benefited every industry as well as themselves; (2) the statutory maxima cannot be exceeded; (3) at many points there is effective sea and canal competition; (4) the result of increasing the rates to a height which prevents the producer from earning a fair profit must, in the long run, be to diminish the traffic of the railway; (5) there is always a liability when, high rates exist that Parliament will sanction a new line, even if the chances of its financial success be not great.