The Triangular Trade, Low Wood & Sedgwick

Roudsea Wood Powder Magazine

Gunpowder from Low Wood and Sedgwick, in South Cumbria, was shipped out to West Africa, to be traded for slaves.

The Triangular Trade was the name given to the system whereby slave ships sailed out of England on the first of the three legs, loaded with trade goods to exchange with West African chiefs for slaves. The slaves were then shipped across the Atlantic to the Americas on the second leg (known as the Middle Passage), to be sold, with the proceeds going to buy sugar and other American goods to be brought back to the home ports of Lancaster and Liverpool on the third leg of the triangle.  These were worth many times more than the trade goods that had gone out on the first leg, thus making vast profits for the entrepreneurs who organised the trade – while of course the ship owners, masters and sailors, as well as all those manufacturing and supplying the trade goods also all benefited from this trade.

One of the major trade goods sent out on the first leg was gunpowder from the mills of southern Cumbria, notably the Sedgwick Gunpowder Mill on the River Kent, which began operations in 1764 – and the Low Wood Gunpowder Mill (Upper Holker) near Haverthwaite, which began in 1798.  Gunpowder was made from three ingredients: saltpetre, sulphur and charcoal.  The first two had to be imported, but the charcoal was made by local charcoal-burners – who thus also were involved in the slave-trade, however remotely.  Saltpetre was the most expensive ingredient, so gunpowder was made in three qualities, with reducing proportions of saltpetre.  The best quality was made for firearms, whether military or sporting, comprising 75% saltpetre, 10% sulphur and 15% charcoal.  The second quality was ‘blasting powder’, mainly for the mining and quarrying industry, which had 70% saltpetre and 15% sulphur – while the poorest quality, known as Africa Powder, contained only 60-65% saltpetre, and so was less powerful, and more likely to misfire.  So, ironically, the African chiefs swapping people for gunpowder were short-changed – they didn’t even get the same quality of powder as the English soldiers – and traders - used.

This side of the South Lakeland Gunpowder industry was relatively short-lived.  In 1807 the Slave Trade Act put an end to the triangular trade, and with that and the end of the Napoleonic Wars, the powder market collapsed.  It began to recover from the 1830s, when the focus switched predominantly to making blasting powder. The Sedgwick site closed in 1852, but re-opened on a new site and continued making gunpowder until 1935. The Low Wood business was damaged by an explosion in 1863 which killed 6 employees: but it continued mainly making blasting powder for coal mining.  After WWI various mergers led to it becoming part of ICI, but it finally closed in 1936.  

Because of the ever-present danger of explosion, finished gunpowder was stored in off-site magazines, with Low Wood using Roudsea, on the Leven estuary, from c1800.  There is a substantial barn currently standing in the Roudsea Wood Nature Reserve, and readily accessible, which probably dates from the early 1800s.  Although it was perhaps originally built for storing oak bark for the tanning industry, it is shown on the First Edition Six Inch Ordnance Survey Map of 1848 as a “Powder Magazine”, as is the original magazine, close by, now used as a summer house.

Photo:  Bark Barn (Powder Magazine), Roudsea Wood

Robert Vickers, The South Lakeland Gunpowder Manufacturing Industry 1764-1936, unpubd PhD thesis, Lancaster University (2003)

Townships: Sedgwick; Upper Holker

Photo and text by Bill Shannon