Re: Water Depth Surveys

Unless you're keen on building things and/or climbing hills, you could
get a lot of the survey info from here:

http://www.nls.uk/digitallibrary/map/early/bathymetric/index.html

Bathymetrical Survey of the Fresh-Water Lochs of Scotland, 1897-1909.
The first comprehensive examination of the depths and nature of 562
inland Scottish lochs, including some 60,000 soundings on 223 coloured
maps.

Images all freely online at National Library of Scotland.

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