For the present edition, the history has been brought to date by adding a chapter on The Tariff Act of familiarly known as the mckinley Act; and the volume has been further enlarged by a closing paper on Some Aspects of the Tariff Question, originally published in the Quarterly ~7'0urual of Economics for April, 1889. That paper has been revised for its present republication, and other parts of the volume have also been revised and rewritten. More particularly, the chapter on The Tariff Act of 1883 has been entirely recast.