Trade and manufactures being considered as servile employments, they had no encouragement to industry; and the numerous spectacles which were exhibited, particularly the shows of gladiators, served to increase their natural ferocity. To these causes may be attributed the final ruin of the republic. The Equestrian order arose out of an institution ascribed to Romulus, who chose from each of the three tribes, one hundred young men, the most distinguished for their rank, wealth, and other accomplishments, who should serve on horseback and guard his person. Their number was afterwards increased by Tullus Hostilius, who chose three hundred from the Albans. They were chosen promiscuously from the Patricians and Plebeians. The age requisite was eighteen, and the fortune four hundred sestertia; that is, about 14,000 dollars. Their marks of distinction, were a horse given them at the public expense, and a gold ring. Their office, at first, was only to serve in the army; but afterwards, to act as judges or jurymen, and take charge of the public revenues. A great degree of splendor was added to the Equites by a procession which they made throughout the city every year, on the 15th day of July, from the temple of honor, without the city to the Capitol, riding on horseback, with wreaths of olives on their heads, dressed in the Togæ palmatæ or trabeæ, of a scarlet color, and bearing in their hands the military ornaments, which they had received from their general, as a reward for their valor. At this time they could not be summoned before a court of justice. If any Eques was corrupt in his morals, or had diminished his fortune, the censor ordered him to be removed from the order by selling his horse. Men became slaves among the Romans, by being taken in war, by way of punishment, or were born in a state of servitude. Those enemies who voluntarily surrendered themselves, retained the rights of freedom, and were called '_Dedititii_.' Those taken in the field, or in the storming of cities, were sold at auction--"_sub corona_," as it was called, because they wore a crown when sold; or "_sub hasta_," because a spear was set up where the auctioneer stood. These were called Servi or Mancipia. Those who dealt in the slave trade were called _Mangones_ or _Venalitii_: they were bound to promise for the soundness of their slaves, and not to conceal their faults; hence they were commonly exposed for sale naked, and carried a scroll hanging to their necks, on which their good and bad qualities were specified. Free-born citizens could not be sold for slaves. Parents might sell their children; but they did not on that account entirely lose the right of citizens, for, when freed from slavery, they were called _ingenui_ and _libertini_. The same was the case with insolvent debtors, who were given up to their creditors.