Admiralty Tidal Stream Atlas : Approaches to Portland - NP257

Admiralty Tidal Stream Atlases In this series the atlases show, at a glance, both direction and rate of tidal streams at hourly intervals by careful and accurate use of graded arrows. Display mean neap and spring tidal rates in tenths of a knot. Include diagram to assist you to calculate the tidal stream rates for your required day.

3rd Edition 1973