Strangely enough, the express companies came to their first prosperity through the thing that they are now forbidden to carry--letters. For in the early forties the United States Post-office Department demanded six cents for carrying a letter thirty miles, eight cents for sixty miles, ten cents for one hundred miles--the ratio steadily progressing until twenty-five cents was charged for 450 miles. Those rates had been in effect since the department was first established, and the service was fearfully slow, and untrustworthy into the bargain. The new express companies took advantage of their opportunity and--to cite a single instance--they would carry a letter from Buffalo to New York for six cents, while the Government charged twenty-five cents for a similar, but an inferior service. In 1850 the express services were beginning to be merged--Livingston & Company and Wells & Company had already formed the American Express Company. Four years later, Adams & Company, Harnden & Company, and some of the smaller express services united in the formation of the Adams Express Company,--and in that year the minstrel men began to ask the question: "For whom was Eve made?" The United States Express Company was also organized in 1854, and all this while Wells, Fargo & Company were forming history for themselves in the Far West--carrying mail out to the gold miners and their precious dust east in return. [Illustration: A PORTION OF THE GREAT DOUBLE-TRACK SUSQUEHANNA RIVER BRIDGE OF THE BALTIMORE & OHIO--A GIANT AMONG AMERICAN RAILROAD BRIDGES] [Illustration: "IN SUMMER THE BRAKEMEN HAVE PLEASANT ENOUGH TIMES OF RAILROADING"] [Illustration: A FAMOUS CANTILEVER RAPIDLY DISAPPEARING--THE SUBSTITUTION OF A NEW KENTUCKY RIVER BRIDGE FOR THE OLD, ON THE QUEEN & CRESCENT SYSTEM]