even keel

Having recently noted the anniversary of the passing away of the tradition of the rum ration with Black Tot Day (31 July 1970)—the abolishment of the daily allotment aboard vessels of the Royal Navy in the UK, though lasting under the admiralties of Canada and New Zealand until 1972 and 1990 respectively, we enjoyed learning about the term “splice the mainbrace”
—originally an emergency directive to undertake one of the most difficult emergency rigging repair jobs, it became over the years an allowance for a taking a celebratory toast or dispensing an extra ration to the crew. Since the institution ended, only the Queen, Admiralty or another member of the Royal Family can issue the order, sometimes with the supplementary command to “Mend and make clothes,” in other words to take half a day off. Compare to the “:59 Minute Rule” that’s observed in the US military that allows commanders to dismiss staff early without charge to leave, since it falls beneath the threshold that requires it.