from The Century Dictionary.
- noun One of the plates of a watch-jewel, against which the pivot abuts.
Sorry, no etymologies found.
We now see very clearly why the hole jewel is made convex on the side towards the end-stone and concave on the side towards the pivot.
The portico was at first built under the slab by pushing an end-stone inwards.
If the hole jewel be of the proper shape, the end-stone not too far from the hole jewel and too much oil is not applied at one time, the oil will not spread nor run down the staff, but a small portion will be retained at the acting surface of pivot and jewel, and this supply will be gradually fed to these parts from the reservoir between the jewel and end-stone, by the action of capillarity.