[1] The powder mill opened around 1740 following the expansion of the port in Bristol and increased availability of saltpetre from India.

The mill was controlled by merchants based in the city and supplied gunpowder to ships sailing from the port.

A previous warehouse, on the site where Bristol Temple Meads railway station now stands was considered too dangerous in the city.

It was powered by an overshot water wheel[8] on Winford Brook a tributary of the River Chew.

[4] The clock tower which was part of the works was originally attached to a chapel or office.