Hi Birdy – welcome to Dartmoor and to this web site. Hopefully also welcome to geocaching!
I have taken the liberty of moving your post to a new topic rather than where you placed it.
Does the cache you found have a name somewhere on the container or on the log book. If so it will be easy to identify. However, from its location it may well be one of the Meldon Mayhem Series.
Anyway, thank you for retrieving the cache and drying it out, hopefully we will be able to identify its owner.