Secret Messages: The Wild TH63 Theodolite

 

 

Chris Gray and Peter Lacovara

While we were surveying in the palace we noticed that the micro-optic screw on the Wild T1 Theodolite we had borrowed from Chicago House was not working well. Luckily we could manage to do most of the survey work needed to establish grids and controls with it, but we still needed to set out the grid for the Main Palace, a task which involved one critical angle. Luckily, Chicago House came to the rescue again and lent us another instrument, a noble TH63 theodolite – a museum piece in and of itself and certainly older than Chicago House! Like our Land Rover, it has a venerable archaeological pedigree, as it had been used by The Oriental Institute during the Nubian Salvage campaign in the 1960’s.

The ancient Chicago House theodolite and its pyramid-shaped container

The sturdy instrument is still in perfect condition after these many years and has its original handmade wooden tripod and ‘waterproof’ metal casing, but none of us knew how to use this arcane instrument. Luckily, and to our amazement, the original handbook was still nestled in the theodolite’s custom-made, pyramid-shaped container. However, the text of the handbook was impenetrable – an early precursor to the unreadable handbooks familiar to all those trying to operate imported TV’s and video players. We were beginning to despair of ever deciphering the cryptic Swiss technical language, when we made a fortuitous discovery. Nestling in a hidden corner of the pyramid box was a set of hand drafted and handwritten instructions lovingly penned (probably using a plume) explaining clearly how to interpret the intricate formulas required to read the angles. It saved the day!

The handwritten instructions we found tucked into the box!