On this day in question Calvus must needs visit his own personal banker, Sextus Herrenius Probus, head of the firm of the Probi, one of the oldest houses on the Via Sacra. Probus is an eques, though his wealth surpasses that of most senators. His father helped such personages as the philosopher Seneca to make and to manage their huge fortunes, but the real origin of the firm went back to Augustus’s settlement of Egypt, when the successful liquidation of the royal estates of Cleopatra provided enormous and lawful commissions. Probus now is practically the Custodian of many of the noblest patrimonies in Rome. He is all the time consulted concerning investments, and Calvus has particularly desired to-day to ask whether his own freedmen are wise in urging their patron (acting, of course, through themselves as middlemen) to put 300,000 sesterces into a transaction in Arabian frankincense. Probus, of course, runs a regular banking business. Besides several junior partners he has a great corps of clerks, some freedmen, and some slaves. His office has all the signs of a well-ordered commercial establishment. Every item of his business is entered in an elaborate system of ledgers, which are regularly brought into court as the most reliable kind of evidence. Such a banker issues bills of exchange on correspondents in such places as Athens, Alexandria, Antioch, Lugdunum, Gades, and even on distant Londinium in Britain. Money is deposited with him, then withdrawn by personal checks (_perscriptio_) in a manner very familiar to another age. On long-time deposits he pays interest; and, of course, he is always loaning money for long or short terms on what seems good security. On the day that Calvus comes to him Probus has just loaned 200,000 sesterces on a mortgage on a well-rented insula, at the standard rate of 12 per cent; and also a sum to a merchant planning a trading voyage to Spain at the heavier rate of 24 per cent until the ships are safe in harbor.[125] Probus, too, exchanges foreign moneys at a fair commission, although by the reign of Hadrian the coinage of all the Mediterranean world has become decidedly Romanized; one seldom now has to change drachmas and shekels into sesterces and _aurei_ (gold pieces), although the old Græco-Oriental coins have not quite disappeared. =203. Trust Business: Savings Banks.=--Besides its strictly banking business Probus’s firm also does much that could at another time be referred to a “Trust Company.” It makes sales or purchases for its clients, undertakes to close up estates, attends to legal business, collects debts, and above all conducts auctions of large quantities of goods in the most responsible manner possible. Somewhat on the side the firm also maintains several small savings banks to attract the sesterces of the humble.