The postmasters enjoyed the monopoly of letting horses to travellers until the middle of the eighteenth century. But the industrial growth of England and the improvement in the roads had produced such an increase in the number of travellers that the postmasters were unable to supply the demand. The use of carriages had become more common, enabling people to travel who could not proceed on horseback, and this had still further increased the demand for horses. It was plain that something must be done and some more extensive source of supply drawn upon than that furnished under the old system. The postmen had heard some of the rumours in the air that a change was about to be made, and they forwarded a petition to the House of Commons, protesting against the contemplated change as an infringement upon their old monopoly. They said "that if the amendment should pass into a law as it is now drawn, it would not only tend to the great damage and loss of the petitioners, but also the prejudice of His Majesty's revenue."[354] The amendment did pass, however, declaring that in future any one might furnish chaises and calashes with horses and that people letting chaises might supply horses for them at the same time.[355] [354] _Jo. H. C._, 1745-50, p. 830. [355] 22 Geo. II, c. 25. In 1779, when the Treasury was sadly in need of money, an act was passed, requiring all persons letting horses to take out licences. In addition, duties were levied on all horses and carriages hired for the purpose of travelling post.[356] In the following year this act was superseded by a stricter and more comprehensive one. It was provided by the new act that every person letting horses to travel should pay five shillings a year for a licence. In addition one penny a mile should be paid for every horse, or, if the distance was not known, 1_s._ 6_d._ a day, such duties to be paid by the person hiring the horses to the postmaster or other person who provided them, to be by him handed over to the Treasury. At the time of payment the postmaster was to give the traveller a ticket, which must be shown to the toll keepers on the road. If he had no ticket to show, the toll keeper was ordered not to allow him to pass.[357] Five years later the duty to be collected was raised to 1-1/2_d._ a mile for each horse or 1_s._ 9_d._ a day.[358] In 1787, permission was given to let these duties out to farm, because so many difficulties had been experienced in their collection.[359] The whole theory of these duties was illogical, for it was to every one's interest to evade them, and direct supervision was impossible. In 1808 another act for farming the post-horse duties was passed, modifying somewhat the provisions of the previous act. The tax was to extend to horses used in travelling, when hired by the mile or stage and when hired for a period of time less than twenty-eight days for drawing carriages used in travelling post. Persons licenced to let horses were required to have