Only letters of great commercial importance could be carried by the new express. They were written on tissue paper, packed into a small, light saddlebag, and passed from rider to rider along the route. The time announced in the schedule was ten days,--two weeks better than Butterfield's best. To make it called for constant motion at top speed, with horses trained to the work and changed every few miles. The carriers were slight men of 135 pounds or under, whose nerve and endurance could stand the strain. Often mere boys were employed in the dangerous service. Rain or snow or death made no difference to the express. Dangers of falling at night, of missing precipitous mountain roads where advance at a walk was perilous, had to be faced. When Indians were hostile, this new risk had to be run. But for eighteen months the service was continued as announced. It ceased only when the overland telegraph, in October, 1861, declared its readiness to handle through business. In the pony express was the spectacular perfection of overland service. Its best record was some hours under eight days. It was conducted along the well-known trail from St. Joseph to Forts Kearney, Laramie, and Bridger; thence to Great Salt Lake City, and by way of Carson City to Placerville and Sacramento. It carried the news in a time when every day brought new rumors of war and disunion, in the pregnant campaign of 1860 and through the opening of the Civil War. The records of its riders at times approached the marvellous. One lad, William F. Cody, who has since lived to become the personal embodiment of the Far West as Buffalo Bill, rode more than 320 consecutive miles on a single tour. The literature of the plains is full of instances of courage and endurance shown in carrying through the despatches. The Butterfield mail was transferred to the central route of the pony express in the summer of 1861. For two and a half years it had run steadily along its southern route, proving the entire practicability of carrying on such a service. But its expense had been out of all proportion to its revenue. In 1859 the Postmaster-general reported that its total receipts from mails had been $27,229.94, as against a cost of $600,000. It is not unlikely that the fast service would have been dropped had not the new military necessity of 1861 forbidden any act which might loosen the bonds between the Pacific and the Atlantic states. Congress contemplated the approach of war and authorized early in 1861 the abandonment of the southern route through the confederate territory, and the transfer of the service to the line of the pony express. To secure additional safety the mails were sent by way of Davenport, Iowa, and Omaha, to Fort Kearney a few times, but Atchison became the starting-point at last, while military force was used to keep the route free from interference. The transfer worked a shortening of from five to seven days over the southern route.