At the end of the 18thC, there were 1768 people living in Lochs, Lewis and 36 of the 845 men were Kelp-Makers.
They produced between 45 and 50 tons of the dark-blue, oily product annually but to do so had to collect 20 times as much of the raw material, sea-weed.
Therefore these 36 men cut and collected between 900 and 1000 tons of Kelp, that is an average of between 25 and 28 tons of this sea-ware per man.
This all had to be laid-out to be dried, then burned for about 4 to8 hours in a Kelp-Kiln, often simply a stone-lined trench.
The weed was next beaten into a mass using ‘kelp irons’ (long-handled iron mallets or hooks), then covered with stones and turf (for protection against moisture), and left to cool overnight.
The pieces of kelp ash would then be broken into lumps ready for ‘export’ to England.
One of these three dozen men was Duncan Macdonald of 6, Old Orinsay, who was my grandfather’s grandmother’s grandfather.
A modern company also harvesting the sea:-ware http://www.hebrideanseaweed.co.uk/history.html