FORTIFICATIONS WORKSHEET ANSWERS – STAR FORT AND CANNON

Deal (photo from Wikemedia Commons) – notice its cannon

CORRECT! Cannon balls would just sink into the earth ramparts of a star fort, so the attackers’ fire would not easily have killed the defenders or destroyed their cannon. Gunpowder is much more powerful than muscle-power, so a cannon can fire a ball a kilometre; an archer could only fire 2-300m. and early hand-guns (‘muskets’) could not fire much further. A large gun, like a cannon, can fire further than a small hand-gun, because air-resistance slows the small musket-ball quicker than the large cannon-ball, so the only weapon to use against a big gun is another big gun (this is still try today, which is why tanks, with their big guns, are still important despite being clumsy and expensive)

The tall walls of made an easy target for cannon; Warwick Castle only survived because it was on the winning side in the English Civil War. There are many ruined castles, such as Kenilworth which were destroyed after with cannon. Medieval castles were not designed to have large cannon, weighing a ton or more, on their walls. Gunpowder also made it much easier to undermine castle walls; only a small tunnel, enough for a some barrels of gunpowder was needed, instead of the big tunnel which medieval attackers needed as they relied on burning the pit-props.

The new designs were low (so they made a small target) and designed for ‘’ so if one layer of the fort was destroyed by cannon, or blown up by a mine, the defenders could retreat to the next layer. As the picture shows, Deal Castle, built by Henry VIII in 1539 has three layers of defences, and a .

The defenders’ cannon would have killed any attackers in the open by firing grape-shot and would have destroyed cannon which were in the open. Attackers would have had to build ‘batteries’ for their cannon (these were small earth ramparts, big enough to protect the cannon and the ‘magazines’ of gunpowder used to fire the shot). To actually attack the fortress, they would have to dig trenches towards it, so the earth protected them: the earth dug out of the trenches was put into big baskets called ‘’ which acted as a when they were full and gave extra protection. This took a long time, as the trenches had to be in a zig-zag; if the trenches pointed straight towards the fortress the defenders could have fired straight down them, so if the attackers started to dig a kilometre away (a safe distance from cannon-shot) they might have to make a trench two kilometres long. When they were close enough, the attackers would come out of the trench and try to storm the fortress.

Deal Castle is one of the few forts designed for cannon in the United Kingdom, as by 1500 England and Wales were a single kingdom, as was Scotland, which united peacefully with England in 1603. By this time the chief defence of the United Kingdom, until the Second World War, was the Royal Navy, (see the Suomenlinna and Pillbox worksheets) and the few defensive British fortifications were built mainly on the coast. In continental Europe there were frequent land wars, especially between France and Austria. Great engineers like the French military engineer developed new and complex designs of fort. They were needed especially in the flat areas between northern France and Russia, and along the Danube valley, where there were no mountains to provide natural defences.

Fort Bourtange (picture from Wikimedia Commons)

Like Deal, Fort Bourtange has three layers of , but they are now all at the same level (so that cannon-balls could not reach the inner layers until the outer bastions had been knocked down), made of earth banks to absorb the impact and separated by , as attackers would easily have climbed the ramparts – if they could have reached them. The only way across the moats is by the thin wooden or by boat, and the plan of the fort was designed so defending cannon could ‘enfilade’ (had a clear field of fire down) each section of the moat. The careful design meant these forts could withstand long sieges – for example, Napoleon’s army never broke through the Lines of Torres Vedras in Portugal.