The class displaced about 3,500 tons at full load and measured 436 feet overall, with a narrow beam and a loaded draft of about 15 feet 7 inches. Those dimensions produced a compact flotilla cruiser but still demanded prudent under-keel clearance in shallow water. The ships used eight Yarrow-type boilers, a description of the pattern rather than proof that Yarrow manufactured every set. Beardmore could reproduce another firm's boiler design accurately even though its own patterns demanded far more maintenance. The distinction shows how British yards spread proven machinery across a multi-yard naval programme.
Notable Point · 7:16-10:31
A compact hull built around Yarrow-type boilers
Dimensions, draft, and boiler choices show how the Arethusa class packed flotilla-leading performance into a small cruiser while British yards worked from a common machinery pattern.