The fragile link between bank credit and stock prices
In the late-1920s stock boom, many investors bought shares with borrowed money. A key source of that credit was call money: short-term loans to stockbrokers that lenders could demand back with little notice. Brokers, in turn, used the funds to help customers buy stocks, often with only part of the purchase price paid upfront.
That arrangement made rising prices seem to reinforce themselves. Investors could borrow to buy shares; as those shares gained value, they could serve as collateral for more borrowing. But the chain depended on lenders continuing to provide credit—and on stock prices holding up.
How a loan call could turn buying into selling
If a lender demanded repayment, a broker needed cash quickly. Customers who could not supply it might have their shares sold to cover their debts. Those sales could push prices down, reducing the value of other investors’ collateral and making lenders less willing to extend credit. More borrowers could then face pressure to repay or sell.
This is the reversal Noyes warned about: the same borrowed money that helped sustain purchases during a boom could intensify a downturn when credit tightened. The danger was not simply that investors owed money; it was that repayment demands could arrive while falling prices made it harder to raise the cash.
A call for repayment did not make a market crash inevitable, and it was not the only force behind the 1929 collapse. But Noyes’s warning identified a vulnerable connection: when stock buying relies on loans that can be recalled, confidence can give way to forced selling—and falling prices can make the debt problem worse.
