International trade has devolved in the 20th century into climate- and resource-controlled exchange between temperate and tropical zones, and intra-temperate zone trade dominated by technology. Nations of temperate zones have been highly inventive of trade-influencing devices. Prospects are that...

The effects of adverse economic conditions in U.S. agriculture upon the structure of farming have been given wide publicity. At the same time but less widely noted, a quiet revolution has taken hold of the ancillary industries supporting agriculture as they struggle to adapt to the changed...