The old private banks in former times used to lend much to private individuals; the banker, as Lord Overstone on another occasion explained, could have no security, but he formed his judgment of the discretion, the sense, and the solvency of those to whom he lent.

And when London was by comparison a small city, and when by comparison everyone stuck to his proper business, this practice might have been safe.

But now that London is enormous and that no one can watch anyone, such a trade would be disastrous; at present, it would hardly be safe in a country town.

The joint stock banks were quite unfit for the business Lord Overstone meant, but then that business is quite unfit for the present time.
This success of Joint Stock Banking is very contrary to the general expectation at its origin.

Not only private bankers, such as Lord Overstone then was, but a great number of thinking persons feared that the joint stock banks would fast ruin themselves, and then cause a collapse and panic in the country.