 The Napoleonic wars and the threat of a French invasion had led to coastal batteries being built as fortifications along the south coast of England in the summer of 1803.Perring was furious to find that a battery had been built on land that he owned at the mouth of the River Yealm in Devon, and wrote to the Secretary of War, Lord Hobart.Perring was eventually pacified by many letters from John Graves Simcoe, who was in charge of the construction of the defences.