river rat
·Since most of you were never in the Navy cross off the watch section idea there were 5 four hour watches and 2 two hour watches per day the 2 hour watches were called dog watches so the reason behind this watch's existence is that, in order for the crew to rotate through all the watches, it was necessary to split one of the watches in half, to create an odd number of watches in a ship's day. This allowed the sailors to stand different watches instead of one team being forced to stand the mid-watch every night. The choice of time also allows both watches, if there are only two, to eat an evening meal at about the traditional time. I am sold on it being a sort of sector clock for tracking aircraft.
https://en.wikipedia.org/wiki/Watchstanding
https://en.wikipedia.org/wiki/Watchstanding
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