Its legality has lately been called in question. It has been supposed to be prohibited by the decision of the Railway Commissioners in the case of the _Denaby Main Colliery Company_ v. _Manchester, Sheffield, and Lincolnshire Railway Company_, which came before them in January, 1880. The complaint was that the rates and tolls charged to the owners of the Denaby Main Colliery, for the conveyance of coal, both by railway and canal were an undue prejudice and disadvantage to themselves and undue preference to the others within the meaning of Section 2 of the Railway and Canal Traffic Act, 1854. The railway rates from the Denaby Main Colliery to Keadby, which is 25 miles, and to Grimsby, which is 56 miles, were 2s. 1½d. and 3s. 1d. per ton respectively. Similar rates were charged from the other collieries in the same group, although the distances between Keadby and Grimsby and the Denaby Main Colliery were 15 miles less than the most distant of the other collieries in the group. For all coal passing to certain places to the eastward, the Denaby Main Colliery was grouped with 48 other collieries in the same district. But, except in certain cases, the collieries were not grouped for coal going to the west; on traffic sent to places in that direction Denaby had to pay according to its geographical position. With regard to some portion of their traffic to the west, the Denaby Main Colliery had special rates. The decision of the Railway Commissioners, which has not been reversed, was that this particular grouping system did subject the proprietors of the Denaby Main Colliery to undue and unreasonable prejudice and disadvantage. But their decision was probably upon the facts, not upon the law; and their finding really was that the group was too large, and that the Denaby Main Colliery ought to be taken out of it. The same question was to some extent discussed in the House of Lords in the _Denaby Main Colliery Company Limited_ v. _Manchester, Sheffield and Lincolnshire Railway Company_ (L.R. 11, A.C. p. 97); and the observations of the learned law lords do not confirm the opinion that grouping is _per se_ illegal.[21] If the contrary were the case--if all such arrangements were necessarily illegal--the result would be somewhat serious to trade. [21] “I think that even if it were distinctly found that the differences in the charges actually made were so disproportioned to the differences in the cost as to be undue and unreasonable, it would not impose an obligation to charge equally.”--Lord Blackburn, p. 122. A few particulars as to grouping on the Continent may be mentioned. It will be found that it has been adopted there for the same reasons as led to it here.