The Falkirk Boat Lift (Known as the Falkirk Wheel) – Ink/Inktense in a Watercolour Moleskine This structure was designed to join the Forth and Clyde Canal to the Union Canal near Falkirk in central Scotland. At this point, the two canals have a difference in height of around 80 feet and, in the past, 15 locks were needed to allow boats and barges to sail from one to another. This strange looking structure, supposedly designed to look like a double-headed Celtic axe, was completed in 2002 and is a brilliant example of all that is good in engineering. Boats sail into the circular openings on the two arms and are sealed in large watertight tanks or caissons. The arms are then rotated until they have completed half a circle then the boats can exit. What is so good about this is that fact that the arms, with their caissons full of water, or with water and boats, are so finely balanced that an incredibly small amount of energy, about enough to boil the water in five kettles, is required to rotate the wheels which are over 100 feet in diameter and weigh many tons. It doesn’t matter if only one boat is being transferred. The caissons still weigh the same, as any boat merely displaces its own weight of water. The building in the background, shaped like a flat segment of fruit, is a comprehensive visitor centre.