About the time which we have mentioned, the imperfection of the statutory classifications became manifest. Such rates as were intended to be _ad valorem_ were not in fact on that basis; so far as it was intended to favour raw produce this object was not sufficiently accomplished. The advantages of differential rates, the necessity of adapting charges to the traffic, the power of railways to open up new districts, and develop new industries, began to be understood. Accordingly the Legislature enacted the following provision, the words of which merit attention:[34] S. 90, “And whereas it is expedient that the company should be enabled to vary the tolls upon the railway so as to _accommodate them to the circumstances of the traffic_, but that such power of varying should not be used for the purpose of prejudicing or favouring particular parties, or for the purpose of collusively and unfairly creating a monopoly either in the hands of the company or of particular parties, it shall be lawful, therefore, for the company, subject to the provisions and limitations hereinafter and in the special Acts contained, _from time to time to alter or vary the tolls by the special Act authorised to be taken, either upon the whole or upon any particular portion of the railway as they shall think fit_; provided that all such tolls be at all times charged equally to all persons, and after the same rate, whether per ton, per mile or otherwise, in respect of all passengers, and of all goods or carriages of the same description, and conveyed or propelled by a like carriage or engine passing over the same portion of the line of railway under the same circumstances, and no reduction or advance in any such toll shall be made either directly or indirectly in favour of any particular company or person travelling upon or using the line.” [34] In the same year a Statute (8 & 9 Vict. c. 28) was passed giving canal companies powers to vary tolls in the same manner as railway companies might. By 8 & 9 Vict. c. 42, which was passed the same session, canal companies were authorised to become carriers on their canals and “to make such reasonable charges for conveying, warehousing, collection and delivery as they might respectively from time to time determine upon, in addition to the several tolls or dues which any such company or undertakers were then authorised to take for the use of the said canals, navigations or railways.” Two years later canal companies were authorised to borrow money for the purpose of becoming carriers on their own waterways. (10 & 11 Vict. c. 94.)