Under the Emperors of Rome, the number of kinds and shapes of vehicles increased; but from the vague manner in which the writers of the period speak of them, it is difficult to enter into minute descriptions. The height of the wheels increased. At the capital of Rome, the Emperor Marcus Aurelius is represented in a car of triumph, the wheels of which are as high as the backs of the horses. Sir William Gell, in his work on the ancient city of Pompeii, which was destroyed in the year A.D. 79, mentions that three wheels had been dug out of the ruins in his day--very much like our modern wheels--a little dished, and 4 ft. 3 in. high, with ten spokes, rather thicker at each end than in the middle. Sir W. Gell also gives a well-known picture of a cart used for conveyance of wine in a huge skin or leathern bag; it is a four-wheeled cart, with an arch in the centre for the front wheel to turn under. The pole in this painting appears to end in a fork, and to be attached to the axle-bed. As the wealth of the Romans increased so did their desire to use comfortable and highly-decorated carriages. For many years what are called “sumptuary laws” existed, which regulated each citizen’s dress, furniture, and ornaments, according to his rank and consequence, and these laws restrained the decorations upon private carriages. The Emperor Alexander Severus, however, issued a decree, “that anyone might decorate his car as he pleased;” and the number of vehicles in use rapidly increased. We find upon monuments many different shaped cars of the time of the Emperors, chiefly processional cars, lofty and highly ornamented, evidently adorned with embossed and chased work in metal, rich carvings, drapery and cushions. On the columns of Theodosius, at Constantinople, are some specially handsome cars on two and on four wheels, with door-like openings in the sides of a square shape. On the arch of Constantine, at Rome, are several cars. Sufficient evidence, however, exists, that for nearly 500 years, during the reign of the different Emperors of Rome, the art of Coachbuilding must have been a good and important business. Besides the ordinary artizans, the woodmen, the wheelwrights, and the smiths, there must have been plenty of employment for the carvers, painters, chasers, embossers, embroiderers, and trimmers.