Such persons do not so much care what is the rate of interest at which they employ their money: they can reduce the interest they pay in proportion to that which they can make.

The vital points to them is to employ it at some rate.

If you hold (as in Lombard Street some persons do) millions of other people's money at interest, arithmetic teaches that you will soon be ruined if you make nothing of it even if the interest you pay is not high.
The fluctuations in the value of money are therefore greater than those on the value of most other commodities.

At times there is an excessive pressure to borrow it, and at times an excessive pressure to lend it, and so the price is forced up and down.
These considerations enable us to estimate the responsibility which is thrown on the Bank of England by our system, and by every system on the bank or banks who by it keep the reserve of bullion or of legal tender exchangeable for bullion.

These banks can in no degree control the permanent value of money, but they can completely control its momentary value.