Those who travelled on them were privileged from arrests in all civil suits.
As the general character of the Roman government was hard and austere, it was particularly so in what regarded the revenue.

This revenue was either fixed or occasional.

The fixed consisted, first, of an annual tax on persons and lands, but in what proportion to the fortunes of the one or the value of the other I have not been able to ascertain.

Next was the imposition called _decuma_, which consisted of a tenth, and often a greater portion of the corn of the province, which was generally delivered in kind.

Of all other products a fifth was paid.