Black, Henry Campbell. A Treatise on the Law of Income Taxation under Federal and State Laws. Kansas City: Vernon Law Book Co., 1913. xlii, 403 pp. Reprinted 2002 by The Lawbook Exchange, Ltd. ISBN 1-58477-237-9. Cloth. $85. * In 1913, the Sixteenth Amendment, which authorized income taxation, was ratified by the required three-fourths majority of states. Black [1860-1927] published this work soon after this historic event in order to define the nature of taxable income, explain the history of income taxation and defend the government's right to impose it. He is guided throughout by a Progressive-Era belief in the federal government as an agent of social reform. Black is also the author of the well-known Law Dictionary.