An examination of the ways in which United States postal policies affected the development of the magazine industry before Congress passed the second-class mail category in 1863 reveals how a medium is shaped at least in part by the technology, policy, and politics of its delivery systems. In the nineteenth century, magazines depended on the mails for distribution more than the other print media, but several obstacles kept them from enjoying the postal privileges conferred on newspapers: (1) as a medium distinct from newspapers, the magazine was relatively new and unfamiliar to policymakers; (2) magazines, pamphlets, and books were thought to be heavier and less transportable than newspapers; (3) magazines lacked the vigorous lobby that safeguarded newspapers' interests; and (4) in a purely subjective judgment, the information purveyed by magazines was deemed less significant and less timely than that contained in papers. The disparity between newspaper and magazine rates prompted publishers to design their publications to resemble newspapers regardless of the content. The postal status of magazines improved by the middle of the nineteenth century because improved modes of transportation accommodated bulkier mails and the post office had grown tired of making fine distinctions among publications. (Author/FL)