Attempts have been made to bring it into more general use, but without success; and it is only in particular circumstances that navigation, with the aid either of locks or inclined planes to surmount the elevations, will not present a more convenient medium for an extended trade."
The early bridges were inclined planes and could easily be crossed by horses.
Several smaller entrances are to be seen in it, as in the south wall: among them one with a series of inclined planes cut in the rock, which leads to an ancient road running south-east to the neighbourhood of the theatre.
The architectural Mexicans, Central Americans, and especially the Peruvians, had no derricks or other hoisting devices, but rolled great stones into place along prepared ways and up inclined planes of earth, which were afterwards removed.
First, no portion of them whatever should be on a dead level, but every part should belong to one or other of a series of true inclined planes.