At the same time, the prætorian leader heard something roll upon the paved road, and immediately a vivid flash blazed under his horse's eyes, and a sharp report followed. Nearly thrown, indeed, he was, as the voice had warned him. When he had recovered his balance and quieted the startled beast he was riding, he halted to listen; but the only sound he could now hear was that of the mounted trooper trotting after him along the Appian Way. He waited for this man to come up, and inquired what he had observed in the three strangers who had previously passed him on the road. "No stranger," said the man, "had passed him; he had seen no one." Then Sejanus remembered what he had not at the moment adverted to, that neither when first accosted by the stranger, nor afterward while this person with his two attendants rode by his side, nor finally when they all galloped forward and were lost in the darkness, had any clatter of hoofs been audible. He resumed his journey in silent thought, and soon arrived, without further adventure, at the large and famous post-house, standing in those days four or five miles south of Formiæ. CHAPTER V. The post house, or _mansio_,[27] to which allusion has been made, situated about four or five miles south of Formiæ, on the Appian road, was a large, rambling, two-storied _brick_ house, capable of accommodating a vast number of travellers. It was not, therefore, merely one of the many relay-houses where the imperial couriers, as well as all who could produce a special warrant for the purpose, from a consul, or a prætor, or even a quæstor, were allowed to obtain a change of horses; still less was it one of the low canal-town taverns, whose keepers Horace abused; but it was a regular country inn, where man and beast found shelter for the apparently infinitesimal charge of one _as_, (or not quite a penny,) and good cheer at proportionably moderate cost. It was well supplied from its own farm-yards, olive-groves, orchards, vineyards, pastures, and tilled fields, with vegetables, beef, mutton, poultry, geese, ducks, attagens, and other meats; eggs, wine, butter, cheese, milk, honey, bread, and fruit; a delicious plate of fish occasionally, an equally delicious array of quail, produced upon table in a state aromatic and frothy with their own fat juices.