This is a common fake fantasy design, it never existed in period. But today it is found in a variety of guises, often being marked 'L/4' 'L/16' and '21' as well as some being unmarked. Designs might vary ever so slightly, but they are all based on the same bogus format. Here's some examples.
'I do not think we can hope for any better thing now.
We shall stick it out to the end, but we are getting weaker of course, and the end cannot be far.
It seems a pity, but I do not think I can write more. R. SCOTT.
Last Entry - For God's sake look after our people.'
In memory of Capt. Robert Falcon Scott, Edward Wilson, Henry Bowers, Lawrence Oates and Edgar Evans. South Pole Expedition, 30th March 1912.