A time indicator comprising a first reservoir (13), a migration medium (11)and activating means for bringing liquid from the first reservoir (13) incontact with the migration medium (11) so that after activation the liquidmigrates through the migration medium (11) producing a colour change therein.The activating means comprises a second reservoir (16) connected between thefirst reservoir (13) and the migration medium (11) whereby after activationthe liquid travels relatively rapidly from the first reservoir (13) to thesecond reservoir (16) and then migrates relatively slowly along the length ofthe migration medium (11) over time.
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