Vernier scale, not too many machinist now a day even know what that is.
Ran an old 6" hoz. gantry G&L mill years ago, that you rode on a platform.
Vernier scale on the hoz. was six to ten feet below with a light on it. You had to look thru a microscope type of lens to focus in and read it from the platform, or climb down close and read it.
Edit: Floor type Hoz mill.
It was also equipped with a DRO, but always like to check the vernier to make sure on the big stuff.
http://fultoniron.net/Don
