German fortification of Guernsey reduce the number and quality of troops required to defend the western ocean areas. Whilst the Luftwaffe and Kriegsmarine had their roles in protecting the islands from the Allies, the occupying forces put their main effort into land defences aimed at repelling a seaborne or airborne assault. The resulting construction work in the Channel Islands was extensive; it required thousands of workers and massive supplies of cement and steel. Tiny Guernsey received special treatment. It had the largest artillery pieces in the Channel Islands, tanks, and 12,000 troops: one soldier for every two civilians on the island, compared to France
History of water supply and sanitation was invented by Alexander Cummings in 1775 but became known as the U-bend following the introduction of the U-shaped trap by Thomas Crapper in 1880. The first screw-down water tap was patented in 1845 by Guest and Chrimes, a brass foundry in Rotherham. Founders of microscopy, Antonie van Leeuwenhoek and Robert Hooke, used the newly invented microscope to observe for the first time small material particles that were suspended in the water, laying the groundwork for the future understanding of waterborne pathogens and waterborne diseases. Sir Francis Bacon attempted to desalinate sea water by passing the flow through a sand