Survey of English Place-Names

Historical Forms

• the Rock Channel 1762 Sheaf

• Rock Perch Battery & Rock Perch Lighthouse 1831 Bry

• Black Rock Lighthouse 1842 OS

• Hoysterlak 1274–81 JRC

• Hostirlach 1275 Sheaf 18

• Hoysterlake 1278–81 JRC

• Hosterlake c.1280(18),c.1285(18) Sheaf

• Pulyord sub Swarteskere 1300–7 JRC

Etymology

Black Rock or Perch Rock (local, Sheaf3 48) (100–308947), Rock Channel & Rock Lighthouse (in Liverpool Bay), the Rock Channel 1762 Sheaf, Rock Perch Battery & Rock Perch Lighthouse 1831 Bry, Black Rock Lighthouse 1842 OS. Orm2 ii 480 reports that about 1828 a new fort of considerable strength was built on the rock near what was formerly known as the Rock Perch , v. perche . The perch was a navigation-mark.The reef which gives name to the lighthouse, the fort and the sea- channel, and perhaps even to Liscard supra , is called The Black Rock 1683 Sheaf3 48 (9807), formerly le skere 1274–81, 1278–81JRC , Swarteskere 1300–7ib , 1308 Misc, Squartesclure 1309 ib, Swerdeskere 1351 BPR, 'the black skerry', v. svartr , sker , blæc , rokke . The colour must be due to seaweed growths, for the stone ought to be red or yellow, cf. Red Noses infra . It was the limit of the port of Frodsham, v. 1308 Misc 46, 1309 Misc 53, 1351 BPR iii7, cf. le Wormehole infra . In the Rock Channel, beside the reef, was a fishery called Hoysterlak 1274–81JRC , Hostirlach 1275 (18) Sheaf, Hoysterlake 1278–81JRC , Hosterlake c.1280 (18), c.1285 (18) Sheaf, 'the oyster stream or pool', from ME  (h)oystre (NED from 1357, cf. OE  ōstre BTSuppl) and lacu or lake . Another, called Pulyord sub Swarteskere 1300–7JRC ('fish-trap in a creek', v. pull , geard , cf. fisc-geard), was an appurtenant of Tranmere manor. In Sheaf3 49 (9189, 9842) it is noted that 'Fishyards'–basket traps–used by Wirral fishermen had blocked the navigation of Rock Channel in 1762, and that they were dredging oysters in Rock Channel in the eighteenth century, at Hoylake in 1754, and taking oysters in Mersey in 1773.