What is "raft bridge"

Raft \Raft\, n. [Originally, a rafter, spar, and fr. Icel. raptr a rafter; akin to Dan. raft, Prov. G. raff a rafter, spar; cf. OHG. r[=a]fo, r[=a]vo, a beam, rafter, Icel. r[=a]f roof. Cf. Rafter, n.]

1. A collection of logs, boards, pieces of timber, or the like, fastened together, either for their own collective conveyance on the water, or to serve as a support in conveying other things; a float.

2. A collection of logs, fallen trees, etc. (such as is formed in some Western rivers of the United States), which obstructs navigation. [U.S.]

3. [Perhaps akin to raff a heap.] A large collection of people or things taken indiscriminately. [Slang, U. S.] ``A whole raft of folks.'' --W. D. Howells. Raft bridge.

   1. A bridge whose points of support are rafts.

   2. A bridge that consists of floating timbers fastened together. Raft duck. [The name alludes to its swimming in dense flocks.] (Zo["o]l.)

      1. The bluebill, or greater scaup duck; -- called also flock duck. See Scaup.

      2. The redhead.

         Raft port (Naut.), a large, square port in a vessel's side for loading or unloading timber or other bulky articles; a timber or lumber port.