Crosby's Complete Pocket Gazetteer of England and Wales or Traveller's Companion (1807)edited by the Reverend J Malham:
Plymouth is a market town seated between the mouths of the rivers Plym and Tamar, in a bay of the English channel, called Plymouth Sound, the Plym passing by one side of the town ,as the Tamar does on the other. The mouth of the Plym is called Catwater and the mouth of the Tamar Ham-Ouse or Hamoaze.
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