External relations of Guernsey both islands retain their independence with regards to domestic affairs but internationally, the islands would be regarded as one state. A Guernsey-Jersey double taxation agreement was first signed in 1956. In 1998 Guernsey and Jersey electricity companies formed the Channel Islands Electricity Grid to operate and manage the submarine cables between Europe and the Channel Islands. Guernsey has formed part of the British–Irish Council since it was formed in 1999, as does Jersey. Meetings take place twice a year, in 2004, 2010 and 2014 the meetings have taken place in Guernsey. Its stated aim is to "promote the harmonious and
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