Possibly the most natural source to turn to in time of war for the increased revenues needed is the existing system of taxes. At first thought it might seem proper to attempt to obtain new income by raising the rates of the old taxes. To some extent this is possible. In every well-arranged tax-system there should be some taxes which can be made to yield an increased revenue by simply raising the rates. One of the chief reasons for the establishment and the retention of the British "property and income tax," for example, is found in the elasticity of the returns. But not all taxes can be treated in this way. Sometimes an increase in the rate of taxation will disturb industry and commerce and do a greater injury to the welfare of the people than is received from the damages of war. Again, an increase in the rates of certain taxes will diminish the revenue or even destroy it entirely. In not a few taxes the only way to increase the revenue is to lower the rates. This is the case with most protective duties. Any change in the rate of such taxes is bound to affect industry and commerce, and to affect them unfavourably in the first instance, whatever the subsequent effect may be. A war brings perplexities enough to business without the creation of artificial ones, and the financier should not interfere with these taxes. It added not a little to the perplexities and dangers of the Civil War in the United States that the industry and commerce of the people were repeatedly disturbed during the war by changes in the tariff as well as by the military and naval operations themselves. There are, therefore, but a limited number of old taxes from which any aid can be sought. In the United States, owing to the one-sided system of federal taxation, the number of them is very small indeed. The American financier must look elsewhere for his new revenues.