The Middle Ages were ignorant of protective taxes. These impediments to the useful exchange of international produce were reserved for the invention and practice of our more enlightened centuries. It is characteristic that the oath which played so great a part in all mediæval transactions, social and political, was also employed to settle the toll dues of the traveller. A crucifix was held before him; on this he swore that he was not defrauding, that the weight of his wares, as stated by him, was accurate, and herewith the transaction was completed. It was, however, necessary to be most careful not to diverge from the toll roads. If a merchant was found on a bye-road his goods were confiscated and he himself imprisoned. On this account, too, companionship was sought after, the leadership of some one familiar with the ground, and hence merchants and merchandize generally moved in caravans. It is worthy of note that all the trade of that time was strictly legitimate, and what is known as real merchant's business. Speculation hardly existed. Commission and agency dues were not wholly unknown, but happily there was not existent that pernicious scourge of modern trade, the time bargains, which permit merchandize to be sold a dozen times over before it actually exists. It was honest, true trade, which only sold what it could show. Therefore, it could uphold and practise the axiom, "ware for ware, or for cash." In certain districts, for example Russia, barter was more common than money payments. Credit was absolutely forbidden in certain towns and in certain branches of trade. If credit was allowed the borrower had to find a surety, and to go surety was a grave matter, of which the consequences might easily prove disastrous, entailing loss of property and often of personal freedom.