Since the establishment of these conditions and rates, there has been a steady and growing increase in the amount of second-class matter sent through the mails. In 1879, under the old rates, the total weight sent at the pound rate was 51,125,500 pounds. In the following year the total weight was 61,822,629 pounds; and by 1910 the total had increased to 817,772,900 pounds, that figure representing an increase of no less than 94,539,718 pounds on the total for 1909. During the whole of this period the accounts of the Post Office in the United States had in two years only (in 1882 and 1883) shown a surplus of revenue over expenditure. In view of the vast quantity of matter sent in the mails at very low rates, the question naturally suggested itself whether, seeing that it was necessary year by year to call on the public treasury for funds to meet the deficiency in the Post Office accounts, it would not be practicable, and equitable, to obtain an increased revenue from this class of traffic. The fact that considerable abuses of the second-class mail privilege had grown up made consideration of the question the more necessary. Periodicals obtained so great a privilege as compared with ordinary books, that publishers sought devious ways to obtain the advantage of the pound rate. Books termed a "library" were issued periodically, with a frequency sufficient to meet the requirements of the Act, numbered in series, and devoted to literature or science; were issued from a known office of publication, and with a list of subscribers. Complying thus with all the requirements of the Act, there seemed no ground on which these publications could be refused admission to the second-class privilege, and they were accordingly entered. The practice grew, and a multitude of libraries, comprising books on every conceivable subject, were distributed through the mails as second-class matter. The Act permitted the posting of sample copies, and as no limit to the number of such copies was fixed, the mails were burdened with vast quantities of sample copies of publications which, while complying with the letter of the statute, as did the "libraries," were in reality mere advertising media. The subscription list was extremely small in comparison with the number of sample copies sent out, and in many cases the subscriptions had been obtained by the offer of premiums at least equal in value to the subscriptions. Another abuse appeared. Under the law, copies of newspapers and periodicals mailed under the second-class privilege which were found to be undeliverable were, when returned to the publisher, liable to postage at the rate of 1 cent for each 4 ounces; but newsagents had the right to send second-class mail to one another, and in order to avoid the higher rate on returned copies, the publishers arranged a scheme by which the copies were returned by one newsagent to another newsagent whose office was near by the publisher's office. These