Scale: Unknown. A model showing the process of making an anchor from bar iron, proposed in 1829, made entirely in iron. The model consists of nine parts that slot together and are held in place by locating pins. The shank is made of six flat pieces of iron, sandwiched together and riveted in three places, that form the overall shape of being square in section with two rounded sides. The bottom of the shank is cut off diagonally and has two rivet holes, one of which has a bolt or rivet within it. The bottom of the shank fits into a corresponding branch piece made in two halves, each made up of six flat pieces of iron, all riveted together. There are four rivet holes, two on the diagonal face and one each on the ends. A small triangular piece fits between the branch and below this fits the crown piece, formed of six flat pieces of iron. There are five rivet holes in the crown piece. There are two identical arms, made up of six flat pieces of iron, with their flukes attached by a single rivet through the palms. There are three loose rivets.