Antique apothecary measures or egg cups.....?
They look like egg cups, turned in boxwood, one end for a hens egg the other for a ducks egg..... but no that is not their purpose. These antique treen pieces are in fact apothecary measurers, made also in silver and pewter. They were made in different sizes and sometimes have numbers stamped on them the largest being 8s for eight spoonfuls and the smallest being 1s. The most common size is the 5s, the size for eggs hence the confusion but in fact the 5s was commonly used for to make soda water. The largest cup was for bicarbonate of soda and the smaller one for citric acid.
These measurers were also used for Seidlitz mixture, this contained three powders tartaric acid, potasium sodium tartrate and sodium bicarbonate used as a digestive and laxative regulator.
Image 1 shows from left to right antique apothecary measurers from 1s, 3s, 5s and a 8s.
Image 2 shows an antique treen measurer on its side so you can see the turning, this is a difficult size to find.
Image 3 shows the largest double measurer in this style an 8s.