series, including a $2 denomination, raising its price to $3.80. Design concepts solicited from various artists won out over Rosewater's suggestions; indeed, the officials of Bureau of Engraving and Printing deemed it imperative for their institutional reputation to produce a series of unquestioned artistic distinction, given that their only previous stamp release, the definitive issue of 1894, had merely been a utilitarian revamping of the 1890 series designed by the American Banknote Company. The new set would have to compare favorably with—- or even better—- the preceding, privately produced Columbian commemoratives. The resulting plan—- more ambitious than the Columbians in one respect—- was to print the Trans-Mississippi stamps with colored frames and black centers, which would have required two separate stages of printing (the Columbians had all been monocolored). During April 1898, however, the Spanish–American War began, and the Bureau of Engraving and Printing—- now required to produce large numbers of revenue stamps—- chose to save labor and press time by printing the Trans-Mississippi designs in single colors after all. This, however, meant that the dies designed for two-toned production had to be retooled (white space surrounding the vignettes had to be filled in with shading that reached the edge of the frames), a process that delayed the release of the stamps until June 17, more than two weeks after the Exposition opened. Philatelic protests notwithstanding, they were received favorably by the general public. They were sold until the end of the year, and postmasters were directed to return unsold stock, which was then incinerated. (Although the numbers printed are known, the numbers returned were not recorded, and so the numbers of existing stamps are unknown.) The stamps, designed by Raymond Ostrander Smith, all have the same shape of frame (a legacy of the bicolor plan); the numerals of value and "UNITED STATES OF AMERICA" at the top; and "POSTAGE" with a spelled-out value at the bottom up through the 50c denomination, the dollar values being in numerals. Ears of wheat and corn appear in odd corners of the frame. Each center design is inscribed with its title: 1¢ dark green – "Marquette on the Mississippi" 2¢ copper red – "Farming in the West" 4¢ orange – "Indian Hunting Buffalo" 5¢ dark blue – "Fremont on Rocky Mountains" 8¢ violet brown – "Troops Guarding Train" 10¢ slate – "Hardships of Emigration" 50¢ olive – "Western Mining Prospector" $1 black –