How a Fulling Mill Works

A technical drawing and a precise description of the mechanics and operation of a fulling mill, from a chapter titled “os pisões de Barroso”, written by Joaquim Fernandes Figueira, in volume XIII of the publications of the Congress of the Portuguese World:

"The model of the fulling mills of Barroso is as follows: an external water wheel with a square oak or chestnut shaft ending in a post or pillar inside the mill or machine. This shaft is crossed by four perpendicular wedges — two for each hammer. These are fixed to the ceiling, one meter apart from each other, and each consists of a thick lever or beam, 2 to 3 meters long, with a block — the hammerhead — embedded at one-third of its length. The “claw” of the hammer strikes a wide and spacious shelf where the fabric to be fulled is placed.
Once the wheel is set in motion, the ends of the levers, where the hammers are attached, strike the wedges on the shaft in alternating transverse motion — first one, then the other — throwing and pressing the fabric against the sides of the shelf, or “gastalha”. It is the impulse of the hammer ‘claws’ that causes the burel cloth to rotate and shift, while the operator occasionally wets it with hot water so the fabric doesn’t ‘burn’ and becomes more compact.
Each piece of burel takes about two hours to prepare, and this service costs five escudos."
(…)"

The fulling mill worker must also stretch the cloth between poles to smooth and dry it, and finally fold the piece to be taken to the markets — especially to the great fair of "S.Miguel (…).”