The culprit is a molecule called gliadin, which is found in certain gluten-containing grains and causes symptoms in gluten-sensitive people. The grains that cause the greatest problems are wheat, rye, barley, spelt, and kamut; whereas corn, rice, millet, and buckwheat are generally considered safe.
The Forth Bridge's piers are constructed from 120,000 cubic yards of concrete and masonry, faced with 2 ft thick granite. 200 trains use the bridge every day, carrying 3 million passengers each year. The total painted area of the Forth Bridge is 230,000 sq metres, requiring 240,000 litres of paint.
It is built with local grit sandstone slabs, weighing up to 1-2 tons apiece. There are seventeen spans, 55 metres in length, set about one metre above the river. [15]. Tarr Steps is a 55 metre long clapper bridge spanning the River Barle at SS 86783211. It is constructed from large slabs of roughly hewn local gritstone, which Grinsell [13] suggests originate from Pickwell Down, and which average 2 - 2.9 metres long, 1 - 1.6 metre wide, and 0.2 - 0.3 metres deep.