From "The Lady's Receipt-Book; a Useful Companion for Large or Small Families" by Eliza Leslie, published by Carey and Hart, Philidelphia, 1846
TO APPLY AN EYE-STONE.--Eye-stones are frequently used to extract motes from the eye, sparks from steam-engines, and other extraneous substances. They are to be procured at the druggists'. They cost but two or three cents a piece; and it is well to get several, that in case one fails you may try another. To give an eye-stone activity, lay it for about five minutes in a saucer of vinegar and water; and if it is a good one it will soon begin to move or swim round in the liquid. Then wipe it dry, and let it be introduced beneath the eye-lid, binding a handkerchief closely round the eye. The eye-stone will make the circuit of the eye, and in its progress take up the mote, which it will bring with it, when on the pain ceasing, the handkerchief is removed. Eye-stones are the eyes of lobsters.
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