While trying to identify new sources of historical marine data I came across some interesting records. They are part of the collection of the Board of Longitude, which is currently held in Cambridge University Library and can be viewed online.
The Board of Longitude was set up by the British Government in 1714 to solve the problem of ships not knowing where exactly they were when out at sea (latitude could be calculated at sea, but not longitude). Some of the content in the Cambridge University Library collection was digitised using funds from the Jisc Content Programme 2011-13, which also funded some of our content digitisation.
There are several observations of tide levels in the collection, including some made in May 1773, in Queen Charlotte Sound, New Zealand. The astronomer William Bayly was on board HMS Adventure, but spent some time ashore taking the tidal measurements.