text:  Again what is to govern the _amount_ at which it is to be fixed? Must it be the additional burden on land? or the price at which foreign countries with their increased facilities of transport and improved cultivation of their soil would be able to deliver it in the British markets? What _data_ have we in either case on which to decide? Let it however always be borne in mind by those who are apt too easily to entertain the question as to either a fixed duty or a total repeal of duty that the advantages predicted by the respective advocates of those measures are _mere assumptions_