The population outgrew the police system. Riots were frequent in times of scarcity or popular excitement, and often could only be quelled by soldiers. Throughout the whole of our period highwaymen infested the roads; in 1774 Horace Walpole at Twickenham declared that it was scarcely safe to venture out by day; Lady Hertford had been attacked on Hounslow Heath at three in the afternoon. Some daring robberies, two of them of mails, were effected in 1791. In the earlier years of the reign smuggling was carried on with amazing audacity, specially on the south and east coasts. It was calculated that 40,000 persons were engaged in it by sea and land, and that two-thirds of the tea and half the brandy consumed in England paid no duty. Bands of armed smugglers rode up to London with their goods, and attempts to interfere with their trade were fiercely and often successfully resisted. Smuggling, however, was checked, as we shall see, by the wise policy of Pitt. The weakness of the police caused an alarming increase of crimes against property; footpads stopped carriages even in Grosvenor Square and Piccadilly, and in 1792 the streets are said on good authority to have been unsafe by night. With the exception of a few Bow street officers and some mounted patrols, the only police in London were parish constables and the watchmen, many of them old and decrepit. The magistracy of Middlesex had largely fallen into the hands of men described by Burke as "the scum of the earth," who used their office as a means of getting gain, and frightful abuses were common.[179] In 1792 parliament established stipendiary magistrates appointed by the crown for the London police courts, and a few police officers were attached to each court. This important reform would have been more effective if a larger number of police had been placed under the orders of the new magistrates, for after that date the police of London and its immediate neighbourhood consisted of not more than 2,044 watchmen and patrols and 1,000 constables and other officers, of whom only 147 received pay and gave their whole time to police work.[180]