Comments by "Lawrence D’Oliveiro" (@lawrencedoliveiro9104) on "Chacha Cipher - Computerphile" video.

@sundhaug92 Probably deleted by YouTube’s anti-spam bot. You can never be sure what it will take exception to. One time I couldn’t even post a link to another YouTube video.
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3:51 When I were a stoont, we had blackboards which were wraparound flexible sheets on rollers. So you just pulled on them to roll on to a new section. Eventually you wrapped round again to the part you previously wrote on, of course, so you had to erase it anyway, but in the meantime it could be left visible as reference.
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