 Complete the following phrase:  The Thames class was a revival of William Batelys design of the Richmond class 32-gun frigate from 1756. The Richmond design was brought back for the Royal Navy in 1804 for the Thames-class frigates because of a desire by the First Lord of the Admiralty, Lord St Vincent, to reduce the amount of timber being used in ships, as well as building costs. The size of frigates had expanded greatly in the period since the Richmond class had been created, and so ships built to its measurements were significantly smaller than other modern designs. The smaller size of the class did mean that their construction could be completed at a faster pace than with larger ships, but design of the ships was held up despite this because of difficulty in locating the original blueprints of the Richmond class. The wartime Royal Navy required increased numbers of and cheaper ships more than it needed larger ships of higher quality, in order to combat the probable 