Although my preference is for long countryside caches, occasionally I encounter things and places in less rural surroundings that I think would make interesting caches. This is a short cache with a straightforward puzzle.
The published coordinates are for Box Post Office, still going strong since the 1800s.
In the later part of the 1800s, postcards came to the fore. Postcards were not just the holiday souvenirs that we are more familiar with now; they were also readily used for local correspondence. Picture postcards were introduced around the turn of that century, a local example of which is shown below.
Things we can clearly see from the postcard are that: it was published by the Box Post Office; it depicts a scene of Box1; it has been franked in Box; and it is addressed to a woman in Chippenham2. This is a genuine postcard; I have not created or doctored it in any way.
1The Blind House, which for a long time had an associated geocache, now archived.
2Langley Fitzurse is an old name of Kington Langley.
What is less clear is the message being communicated. However, although this may befuddle an Edwardian postman, most geocachers will make short work of it.
- Decipher the message.
- Using this information, deduce a full date for the secret tryst.
- Furthermore, let us assume that the time of the assignation will be precisely half-past 6 in the evening (assume GMT).
- Using this time and date, calculate the equivalent unix epoch time, ignoring the negative sign.
"What is that?" I hear all non-programmers exclaim, "We thought this was supposed to be a straightforward puzzle!"
Don't worry, just web-search it and/or use a converter such as this one. We just needed a way to get a string of digits that we can assign to ABCDEFGHIJ, to then use in this formula for the location of the couple's rendezvous:
N51 24.(F−G+H)(E+G)D
W002 15.G(D+F−B)(F−H)
You can check your solution and receive a hint for GZ here.
No spoiler photos at GZ please.