in epic and dramatic poetry, is when the poet introduces the use of machines; or brings some supernatural being upon the stage, in order to solve some difficulty or to perform some exploit out of the reach of human power.

The ancient dramatic poets never made use of machines, unless where there was an absolute necessity for so doing; whence the precept of Horace,

Nec Deus interfit, nisi dignus vindice nodus Inciderit.

It is quite otherwise with epic poets, who introduce machines in every part of their poems; so that nothing is done without the intervention of the gods. In Milton's Paradise Lost, by far the greater part of the ac- Machinery tors are supernatural personages: Homer and Virgil do nothing without them; and, in Voltaire's Henriade, the poet has made excellent use of St Louis.

As to the manner in which these machines should act, it is sometimes invisibly, by simple inspirations and suggestions; sometimes by actually appearing under some human form; and, lastly, by means of dreams and oracles, which partake of the other two. However, all these should be managed in such a manner as to keep within the bounds of probability.