On Rotary Inventions
In the early years of the twentieth century a largely forgotten fourteen-year-old apprentice blacksmith named Gilbert Toyne made one of the great contributions to Australian technology, displaying the initiative and inventiveness that would make the southern continent great among nations. He invented a height-adjustable rotary clothesline. Called off to war in 1914, Toyne's invention was more successfully marketed by a certain Lance Hill and became ubiquitous in Australian suburbia, and popularly known as the Hills Hoist. It was the Australian equivalent of such American marvels as the Ferris Wheel, chocolate chip cookies and dental floss, a fixture in every backyard, a thing of pride for every Australian housewife and a shining example of growing prosperity and marketing initiative. Its fame was such that the National Library of Australia has listed the Hills Hoist as a National Treasure alongside Captain James Cook's Journal from HMS Endeavour, the helmet of the famous bushranger Ned Kelly, Sydney Opera House and the lyrics of Waltzing Matilda.
Seven hundred years before Toyne's invention, another inventive mind similarly designed a rotary creation that was to have a rather more dramatic, if less widespread and long-term, influence on history. At the end of May 1218, the fleet carrying the army of the Fifth Crusade arrived opposite Damietta at the mouth of the Nile. There they got bogged down for four months, their advance down the Nile inhibited by the presence of a strong tower situated in the middle of the river that could not be mined and was strong enough to withstand bombardment by the crusaders' ballistic machines. Attempting to reach this tower by ladders raised on board their ships, the crusaders came under attack by stone missiles and Greek Fire and many knights fell into the river and to their deaths in this futile attack.
The day was saved by the inventiveness of the chancellor of Cologne, Oliver of Paderborn, with the aid of some industrious Frisian crusaders. In a letter to Pope Honorius III in September of that year, James of Vitry, the bishop of Acre, described the manner in which this was achieved. Oliver directed his men in creating a "wonderful hitherto unknown war machine":
"They tied together two ships at great expense (2,000 marks) and effort. On it the built a rotatable bridge on which they put a ladder and a fortification to protect the whole machine."*
After another attempt to scale the tower failed when the upper part of the ladder was burnt and one knight fell to his death, the rotary bridge was put to use. It enabled a large number of crusaders to reach the tower, surround it and set fire to its door. Ten crusaders entered, killing two hundred and fifty Muslims and the tower was surrendered to the Christians.
According to the bishop of Acre, the tower at Damietta was key to the whole land, so this conquest was potentially a highly significant event, though sadly (for the crusaders) it did not result in the long-desired and ever elusive conquest of Egypt. Consequently, Oliver's rotary invention did not become the "turning point" in crusader history that would surely have earned it a place on the list of crusader National Treasures.
*Malcolm Barber and Keith Bate (trans.), Letters from the East. Crusaders, Pilgrims and Settlers in the 12th and 13th Centuries, Ashgate, 2013, pp. 113-4.