Edition 4 1993. This edition of NP 337 has been reschemed to a larger scale to depict Tidal Stream information for the western and eastern approaches separately. There is an overlap covering the area between Cowes and Stansore Point and the western limit abuts to the eastern limit of NP 257 Approaches to Portland. This atlas contains two sets of 13 charts showing tidal streams commencing 6 hours before HW Portsmouth and ending 6 hours after HW Portsmouth. The total area covered stretches from St. Alban's Head to Littlehampton and includes the whole of the Isle of Wight.