KENILWORTH CASTLE. 1918 South Africa 1d postal envelope to a soldier in Egypt with a Pietermaritzburg 25 APR 18 cancellation. This cover was on the ill fated Union Castle 'Kenilworth Castle' that was in a collision with an escorting destroyer in the Solent off Southampton on the night of 4 June. Two depth charges rolled off the destroyer and exploded under the Kenilworth Castle causing major damage. The ship was beached and salvage started on 6 June. Various cachets were applied to the recovered mail, the one on this cover being among the rarest. - probably as it was going to an unusual destination for mail off the ship. R. E, Postal Section L don N.W. 1 / Damaged by immersion / in sea water. This differers to a similar cachet illustrated in Hoggarth & Gwynn with 'Section' being printed in full – whereas in the book it is abbreviated to 'Sect.' To date this is the only cover recorded with this particular cachet. The cover has water staining around the edges, which is normal for recovered mail. An important cover from this incident.