ABSTRACT
The Duration of Tide (DOT) will be the DOT at the Secondary Port after the time differences have been applied. Once again this leaves either the Height of Tide, or the Time Interval to be derived, depending on the nature of the problem to be solved. The only difference which needs to be appreciated is that in the Pacific Ocean, Secondary Ports may have their Standard Port not just hundreds of miles away, but in some cases thousands of miles apart. The connection between the two ports is not geographical but the characteristic of the tidal flow. It will now require more care to ensure the significance of the differences in the Time Zones between the two ports, when choosing the appropriate pair of tides when commencing the calculation. Time differences between Pacific ports are often now considerably larger than with most European Secondary Ports.
