ClipArt ETC
"An animal of one of the lower orders. It fastens itself to some floating object and becomes glued to it by a secretion of cement, and develops a valved shell."

Barnacle

"An animal of one of the lower orders. It fastens itself to some floating object and becomes glued to…

"The following cut will show specimens of ancient clasps." — Anthon, 1891

Ancient clasps

"The following cut will show specimens of ancient clasps." — Anthon, 1891

An iron bar with ends bent over and pointed, for securing logs together in a raft. The points are driven respectively into adjacent or juxtaposed logs, which are thus bonded to each other.

Raft Dog

An iron bar with ends bent over and pointed, for securing logs together in a raft. The points are driven…

A mechanical fastener.

Rivet

A mechanical fastener.