We think of and use indexes more often in conjunction with locating secondary periodical literature. However, primary source material can be found in periodical articles, too.
Making of the Modern World (database just above) is the digital product containing full texts of the Goldsmiths’-Kress Library of Economic Literature to 1800. We have it on microform (Remote Storage #16416 and #16416a) and index in DMC 4th floor West Wing Z 7164 .E2 G63 1997. The content is works in English and other Western European languages about business and economics, political theory, social conditions, emigration, slavery, population, commerce, trades and manufactures, finance, transport, and agriculture.