=Deposit of United States Funds.=--The taxes collected by the national government, together with its other funds, are kept partly in the treasury and partly in the nine subtreasuries located at Baltimore, Boston, Chicago, Cincinnati, New Orleans, New York, Philadelphia, St. Louis, and San Francisco. In addition the secretary of the treasury is authorized to designate national banks as depositories and to deposit certain of the funds therein. In times of financial stringency or threatened crises, this authority may be used by the secretary to relieve the money market, by distributing the public funds among the depositories. =Federal Appropriations and Expenditures.=--Having studied the sources of federal revenues, we come now to the subject of expenditures. Revenue bills are prepared, as we have seen, by the ways and means committee of the house of representatives. At first the appropriations of Congress were embodied in a single bill prepared by the committee on appropriations, but as the operations of the government expanded, the appropriations came to be embodied in a number of bills, sixteen in 1920, prepared by nine different committees. The committee on appropriations was responsible only for the half dozen more general appropriation bills, while other committees prepared the the bills appropriating large amounts for the army, navy, diplomatic service, post office, Department of Agriculture, District of Columbia, Indian service, and improvement of rivers and harbors. In 1921, however, the committee on appropriations was enlarged and again entrusted with the preparation of all the various appropriation bills, the house thus returning to the earlier system of a single committee responsible for all expenditures. The growth of national expenditures has been rapid. The appropriations for 1916 reached the unprecedented amount of $1,637,583,682; those for the period of the war (1917-1918), $32,427,000,000, including $9,000,000,000 loaned to European allies. In 1921, the appropriations were reduced to about $5,500,000,000. =The National Debt.=--Whenever the revenues of the government are insufficient to pay its expenses recourse must be had to increased taxes or loans. In time of peace the ordinary revenues ought to be sufficient to meet expenses, but when extraordinary expenses must be incurred as is the case when war breaks out, or foreign territory is purchased, or some great public work is to be constructed such as the digging of the Panama Canal, the government must have recourse to the borrowing power. The Constitution of the United States expressly confers upon Congress the power to borrow money on the credit of the United States, and no limitations whatever are placed on the exercise of the power, such as are generally imposed on state legislatures by the state constitutions.