The lower casemate guns were just a few feet above water, making them impossible to use in heavy seas.
The compilers of The Naval Annual revised costs quoted for British ships between the 1905 and 1906 editions.
Following the outbreak of World War I, the ships were primarily tasked with combating German commerce raiders, patrolling in both the North and South Atlantic.
HMS Monmouth was assigned to Rear Admiral Sir Christopher Cradock's squadron, and was sunk at the Battle of Coronel in November 1914.
HMS Kent continued the pursuit of the light cruiser Dresden, eventually locating her and forcing her to be scuttled at the Battle of Más a Tierra.