The last form of taxation, that of an excise upon licenses or trades, is most usual in the South.  An increasing number of trades are thus being taxed or regulated.  Sometimes the taxation is put under the guise of a fee for examination and licensing, sometimes plainly as an excise tax.  Undoubtedly such taxation is against all the history of our legislation demanding complete freedom of labor and trade.  Nevertheless, it has not been held unconstitutional by the States except, of course, when touching a trade which is interstate commerce, though the examination occasionally has been.  Such taxation has not yet become popular in the North, except definitely for the purpose of examination and license; but it is almost universal in the South, many States indeed providing by their constitution or laws that all trades and callings may be thus taxed.  These taxes may be arbitrary in amount, but are sometimes graded according to the amount of business done.  Such legislation has been sustained in so far as it is a tax or a license imposed for protecting the public health in a reasonable manner; thus, doctors, plumbers, nurses, dentists, etc., have been submitted to such regulation, but in the case of blacksmiths its constitutionality was in one State denied, and the law as to barbers in several States annulled.  Nevertheless, it will always be a popular method of raising money in the poorer States, where land already bears its full burden and little personal property can be found.

Commissions of inquiry on this whole subject of taxation are continually being appointed—­we have had two in Massachusetts in the past ten years—­and their recommendations nearly always prove unacceptable.  The probable scientific answer, that you must only tax property and not money or the evidence of property, and that if direct taxation thereby becomes too burdensome we must reduce our rate of expenditure, is a conclusion our legislators are yet unwilling to accept.  The taxation of corporations presents a different problem and we shall therefore leave it for special consideration with that subject.  The matter of betterment taxes may be dismissed with a word, as it is hardly, in theory, taxation at all, but rather using municipal agencies to collect the cost, or part of the cost, of a local work or benefit.  It is, of course, closely connected with the subject of eminent domain.  That is to say, only a public use, or at least a general local benefit, can justify a betterment tax.  There is still considerable legislation on this matter, confined generally to the objects of securing a jury trial, or at least a public hearing, on the amount of the assessment, defining the purposes for which it may be imposed, as, for instance, paving, sewers, water-works where public, and—­perhaps the most contested case of all—­that of parks or pleasure-grounds; and providing that the amount of betterment taxes imposed shall not exceed one-half the value of the improvement of the property, and shall never exceed the amount paid as damages when part of the owner’s land is taken.