the four "bramble"-class gunboats were designed to protect the far-flung outposts of great britain's colonial empire. at 180 feet long and 33 feet in beam, with a draft of just 8 feet and a displacement of only 710 tons, they were the smallest seagoing vessels built for the royal navy in the 1890s. they were also among the cheapest, built at a cost of just over £50,000 each, less than 5% of the cost of a contemporary battleship.