Antique  19th century boxwood double cup measurer. This one is the smallest and equates to 1s - one teaspoon. The more common sizes are the 3s and 5s sizes.
They were used by apothecaries, chemists and domestic purposes.
C1870
 
It measures 6.5cm h x 2.5cm w at the narrowest end and 4cm w at the bigger end.