TUBE SideTracked - Perivale
As you arrive here, soaking in the architectural design of this Grade II listed station building, notice three big numbers at either of the front entrances. They followed the letter “G”: let’s call them ABC.
This is a simple offset multi: increase the northing of the published coordinates by (A-B), and westing by AxAxC/B.
The cache is comfortable in its home, but it is somewhat high, so you will need a bit of a stretch. Its tummy contain a small piece of log paper – and you may need tweezers to extract it. Please bring a pen to sign, too.
Optional: it would be great to hear, in your find logs, any tube stations that you find interesting in their architectural designs.
You can check your answers for this puzzle on GeoChecker.com.