There is no part of this rapid development of the business more interesting than the commercial machine the oil men had devised by 1872 for marketing oil. A man with a thousand-barrel well on his hands in 1862 was in a plight. He had got to sell his oil at once for lack of storage room or let it run on the ground, and there was no exchange, no market, no telegraph, not even a post-office within his reach where he could arrange a sale. He had to depend on buyers who came to him. These buyers were the agents of the refineries in different cities, or of the exporters of crude in New York. They went from well to well on horseback, if the roads were not too bad, on foot if they were, and at each place made a special bargain varying with the quantity bought and the difficulty in getting it away, for the buyer was the transporter, and, as a rule, furnished the barrels or boats in which he carried off his oil. It was not long before the speculative character of the oil trade due to the great fluctuations in quantity added a crowd of brokers to the regular buyers who tramped up and down the creek. When the railroads came in the trains became the headquarters for both buyers and sellers. This was the more easily managed as the trains on the creek stopped at almost every oil farm. These trains became, in fact, a sort of travelling oil exchange, and on them a large percentage of all the bargaining of the business was done. The brokers and buyers first organised and established headquarters in Oil City in 1869, but there was an oil exchange in New York City as early as 1866. Titusville did not have an exchange until 1871. By this time the pipe-lines had begun to issue certificates for the oil they received, and the trading was done to a degree in these. The method was simple, and much more convenient than the old one. The producer ran his oil into a pipe-line, and for it received a certificate showing that the line held so much to his credit; this certificate was transferred when the sale was made and presented when the oil was wanted.