Until almost the twentieth century, one simple tool constituted the primary earth moving machine: the hand shovel – moved with animal and human powered, sleds, barges, and wagons. This tool was the principal method by which material was either side cast or elevated to load a conveyance, usually a wheelbarrow, or a cart or wagon drawn by a draft animal. In antiquity, an equivalent of the hand shovel or hoe and head basket—and masses of men—were used to move earth to build civil works. Builders have long used the inclined plane, levers, and pulleys to place solid building materials, but these laboursaving devices did not lend themselves to earth moving, which required digging, raising, moving, and placing loose materials. The two elements required for mechanized earth moving, then as now, were an independent power source and off-road mobility, neither of which could be provided by the technology of that time. Container cranes were used from the 1950s and onward, and made containerization possible. Nowadays, such is the importance of this machinery, some transport companies have developed specific equipment to transport heavy construction equipment to and from sites.