Complex sentence: Dance hoped to persuade Linois that his ships included some fully armed warships and he therefore ordered the brig "Ganges" and the four lead ships to hoist blue ensigns, while the rest of the convoy raised red ensigns.
Split into simpler sentences: Dance hoped to persuade Linois that his ships included some fully armed warships. He therefore ordered the brig "Ganges" and the four lead ships to hoist blue ensigns, while the rest of the convoy raised red ensigns.