Theres a good book called invisible on Everest, which has quite a bit about Grenfell cloth. Invented by Walter Haythornethwaite, in 1923, named after Sir Walter grenfell, a labrador missionary. He visited a lecture by Sir Grenfell and heard their was a need for a light, windproof, water resistant, breathable cloth. The book states there was Burberry around, which was similar. However, to make this Grenfell cloth required special looms with skilled operators. It was a very high quality and very expensive cloth.
The same book also mentions that Haythornethwaite produced 5 million square yards of cloth for the armed forces during WW2. Then, due to a cotton shortage , any mills not involved with war work, were shut down. Even though Haythornethwaites mills were doing 84% war work, they were shut down. This was 1941. It looks like the main reason was a problem with relations between him and the Ministry of Supply, as he was very short tempered, apparantly!! In 1941 the Shirley institute invented ventile, and this took over!
On another note, I bought a smock from SASS, in a very high quality gaberdine that the owner got from the states, might be similar to Byrd cloth. Its amazingly water resistant, more so than my old ventile smock. it doesnt stiffen when wet. Not sure if they still have any, but they are far supperior to the standard gaberdine used in the SAS type smock.
Be interested to know if Grenfell cloth stiffens when wet , like Ventile? I think they may work on different principle, where ventile fibres swell to stop water getting in, so seem to 'wet out'. Anyway, highly recommend these SASS smocks made in this quality cloth. Mines in plain desert colour, but they do a green, which would be good.
