& Brown have bought wheat at $1.39 and the market closes
at $1.35 they lose four cents per bushel on their purchase and must
settle the difference with the Clearing House. All differences between
buyers and sellers must be settled each day and if the volume of trades
has been heavy, the Clearing House staff work on their books--all
night, if necessary--until everything has been cleared for next day's
business. The firm which loses to-day may gain by to-morrow's trades,
maintaining good average business health. Any private trading which
may take place after official trading hours is known as "curb" trading.

The rules of the Clearing House are very strict. Any firm which fails
to report by two o'clock is fined. The Clearing House assumes
responsibility for all purchases and sales and, being actually liable,
keeps close tab on every firm. Each firm has a certain credit on the
books of the Clearing House, allotted impartially, according to its
standing, and this credit forms the fixed basis of that firm's
dealings. If its activities exhaust the line of credit, the Clearing
House calls for "original margins" at once--a deposit of so-many cents
per bushel for every bushel involved and for every point which the
market drops. The amount per bushel called for is entirely at the
discretion of the Clearing House authorities and if the quantity of
grain reaches dangerous proportions the deposit required may be set so
high that it becomes practically equivalent to cash purchase. To
"corner the market" under these conditions would require unlimited
credit with the Clearing House.

When Jones & Brown are "called" for deposit margins they drop
everything and obey. They have just fifteen minutes to reach the bank
with that cheque, have it "marked" and rushed to the Clearing House.
If they fail to arrive with it the Manager of the Clearing House will
step into their office and if there were any "hemming and hawing" Jones
& Brown would be reported at once to the Secretary of the Exchange who
would call a hurry-up meeting of the Exchange Council and Messrs. Jones
& Brown would find themselves posted and all trades with them forbidden.

All clerical errors in regard to trades are checked up by the Clearing
House and fines paid in for mistakes. Only a nominal charge is made
for its services--enough to pay overhead expenses--but the fines have
enabled the Clearing House to accumulate a large Reserve Fund which
gives it financia