Mary, Queen of Scots was not the only one who used a complicated “letterlocking” process to conceal the contents (Mary, Queen of Scots ‘locked’ final letter using paper-folding, research finds, 10 December). My mum, now aged 98 and the mother of eight children, used to write notes for us to give to our teachers excusing sickness absences and folded them in a way that we could not open or see what she had written. We thought it was either to save the cost of eight envelopes, as invariably we passed our illnesses to each other, or that she was telling the teacher that really there was not much wrong with us.
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