"Once the brokerage house, rather than the bank, became the locus for American savings, that money would find its way into the stock market, because the broker was someone with a much higher tolerance for risk than the banker"

This quote by Ron Chernow is referring to the shift in the American economy from the conventional banking system to the brokerage home system. This shift meant that individuals's savings were no longer held in banks, but rather were invested in the stock exchange through brokers. This shift was considerable because brokers had a much greater tolerance for danger than bankers, indicating that individuals's savings were more likely to be invested in higher risk, greater benefit stocks. This shift in the economy enabled more people to buy the stock exchange, and for more cash to be purchased the stock market in general. This shift has had a lasting effect on the American economy, and has permitted more individuals to take advantage of the stock market.