Paul says hi ! The ladder to the right is actually a track for the gasoline powered lift that raises the stones and "mud" up to the stonemason. Without the lift, this project would be much more difficult. It's powered by a 3.5hp Briggs-and-Stratton motor.
In the picture above, you can see the raw stone that we're cutting and chiseling to make the pitch face stones for the tower. Most of the stones are 8" to 10" thick. By splitting them (or sometimes cutting them) in half, with the grain, we get stones that are about 4" thick (+- 1"). We then work that material into random lengths. I also cut specific length stones the mason needs to finish a course at the corners and windows (as he's laying them).
The mortar is wet in some of the joints in this picture. After it dries a bit, the mason will rake the joints with a wire brush, then with a soft brush.