326 HAR YARD LA W RE VIE W. legislature has been permitted to go to the extreme limit of the law, and all these decisions have clearly recognized the principle that taxation can only be for a public purpose. The difficult case is neither that of a public expenditure for the equal general benefit, nor of a public expenditure with inci- dental private advantage, but that of an expenditure for the direct benefit of individuals with an incidental public gain. In other words, it is not the case of the highway for the general good, nor of one owned and enjoyed by the public while incidentally afford- ing exceptional private benefit. It is, as it were, building private avenues at public expense, from which individuals directly bene- fited exclude the public, in order that the public may derive inci- dental advantage from the increased prosperity of the individuals benefited, through their enhanced ability to pay wages or taxes upon increased valuations. 1 Cases, indeed, may be supposed in which this incidental public gain is actual, and productive of im. mense general advantage ; an advantage sufficiently great to make the original investment of public money profitable, in the business sense. Apparently, it is this class of cases which we are consider- ing in these sugar bounties. Is such an expenditure for a " public purpose " ? This question the uniform current of authority in State and Federal courts has answered in the negative. As relates to State governments, tax appropriations for the direct benefit of indi- viduals to reach an incidental public advantage are beyond the legislative power. Whether the same rule applies to Congress will be considered later. But in State affairs, wherever the inces- sant activity of those who ask direct private gain under promise of indirect public advantage is incorporated into legislation, such legislation is void. Under any of its Protean forms, however dis- guised, if it can be detected that an application has been made of public moneys for the primary benefit of individuals, courts have shown themselves astute in following and defeating the substance of the arrangement. The language of these cases is free from ambiguity. They are familiar, but worthy of review. In citing them we avail ourselves of the careful summaries contained in the briefs of the importers' counsel. In Massachusetts a well-considered opinion is that given in the leading case of Lowell v. Boston (in Mass. 454). 1 See Morse v. Stocker, 1 All. 150.
