Please note that Mommsen uses the AUC chronology (Ab Urbe Condita), i.e. from the founding of the City of Rome. You can use this reference table to have the B.C. dates
From: The History of Rome, by Theodor Mommsen
Translated with the sanction of the author by William Purdie Dickson
In transmarine transactions more especially and such as were otherwise attended with considerable risk, the system of partnership was so extensively adopted, that it practically took the place of insurances, which were unknown to antiquity. Nothing was more common than the nautical loan, as it was called--the modern "bottomry"--by which the risk and gain of transmarine traffic were proportionally distributed among the owners of the vessel and cargo and all the capitalists advancing money for the voyage. It was, however, a general rule of Roman economy that one should rather take small shares in many speculations than speculate independently; Cato advised the capitalist not to fit out a single ship with his money, but in concert with forty-nine other capitalists to send out fifty ships and to take an interest in each to the extent of a fiftieth part.
The greater complication thus introduced into business was overcome by the Roman merchant through his punctual laboriousness and his system of management by slaves and freedmen --which, regarded from the point of view of the pure capitalist, was far preferable to our counting-house system. Thus these mercantile companies, with their hundred ramifications, largely influenced the economy of every Roman of note. There was, according to the testimony of Polybius, hardly a man of means in Rome who had not been concerned as an avowed or silent partner in leasing the public revenues; and much more must each have invested on an average a considerable portion of his capital in mercantile associations generally.
All this laid the foundation for that endurance of Roman wealth, which was perhaps still more remarkable than its magnitude. The phenomenon, unique perhaps of its kind, to which we have already called attention(27)--that the standing of the great clans remained almost the same throughout several centuries--finds its explanation in the somewhat narrow but solid principles on which they managed their mercantile property.
27. III. XIII. Religious Economy
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