Ship track information is missing for this map. 4 is the track information for a region around the Cape Verde Islands. The masking of information from the vicinity of the islands is worrysome. While I have not made use of ship track information as yet, the possibility that it may be be incomplete would make an assessment of the quality of nearby bathymetry impossible. Finally, some of the digitized coastlines do not close around islands.
Closure quality seems to vary with the region.
There were no difficulties with the data making up Fig. 3. Repair of each of the gaps manually would be tedious for large areas. The digital atlas is very easy to access and is complete. With the program I wrote, it takes me about five minutes to extract the data from the CD-ROM and to generate a map. It is a handy research data source that many earth science disciplines could profitably use.