Anvil - (Webster's 1828 Dictionary)
AN'VIL, n. [The Latin word incus, incudis,is formed by a like analogy fromin and cudo, to hammer, or shape.]
An iron block with a smooth face, on which smiths hammer and shape their work.
Figuratively, any thing on which blows are laid.
To be on the anvil, is to be in a state of discussion, formation or preparation; as when a scheme or measure is forming, but not matured. This figure bears an analogy to that is discussion, a shaking or beating.