Whaling logs sometimes note the time system that they have adopted when at sea, or when in port (nautical or civil as shown in the grid below). When no system is noted it is a case of trawling the log for sufficient indications to determine the system used.
Rarely, some whalers state their own specific start time, for example, 1 PM or 6 PM ("after supper at 6 PM"). The primary worksheet in the transcription workbook will state the time system. If you find it to be otherwise, please post that information in the Shipyard for your whaler.
Most whaling logs split the day into first, middle, and latter parts.
Whaling ships
![Image](https://imgur.com/Merc7SI.png)
For a slightly longer explanation see Telling the time in whaling logs