Nautical chart of  Hoy Sound. Surveyed by Mr. George Thomas, Master, assisted by Lieut. F.W.L. Thomas &amp; Mr. J. Wells, Master, 1842. Not current - not to be used for navigation!
<bdi><a href="https://en.wikipedia.org/wiki/en:United_Kingdom_Hydrographic_Office" class="extiw" title="w:en:United Kingdom Hydrographic Office"><span title="UK government agency concerned with providing hydrographic and marine geospatial data">United Kingdom Hydrographic Office</span></a>
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