Mercury Compositions on Aluminium Alloy Hull Plating

The action of many anti‐fouling compositions is fortified with small amounts of mercury compounds averaging about 3% calculated as mercuric oxide. Publicity has been given to the effect that mercury‐containing paints should not be used on the bottoms of aluminium alloy craft because of the harmful effect then produced. Nevertheless, this warning has not always been heeded and the present article describes the examination of an aluminium alloy motor‐boat, the hull of which had been treated with an unsuitable composition. The results should be of interest and value not only to those concerned with the building and maintenance of aluminium alloy craft but also to metallurgists and engineers in a wider field.