Note 21 — EPITOME OF GALVANISM.
Reading edition
This sub-acid taste, is rendered much more distinct by an instrument invented by Professor Robinson, and described by him in a letter to Dr. Fowler, dated 28th May, 1793. It is made by placing alternately a number of small circular pieces of zinc, with as many pieces of silver of the same size, in the form of a rouleau. It is to be used by placing it laterally upon the tongue.