The Salt Shaker: Wires Under the Cap That Break the Lumps

"My invention relates to salt-holders for table use having a cap with apertures through which the salt is ejected, and means within the holder to prevent the salt from consolidating in a mass or in lumps". "Heretofore various devices have been placed in salt-holders to prevent the salt from adhering to the sides thereof. They consist most commonly of a single rod, terminating in a pronged portion ... but these devices have been only partially successful in securing a proper delivery of salt." The cap has "a series of apertures, b', through which the salt is ejected, and between these apertures are soldered or otherwise attached to the under side of the cap B a series of parallel wires, b2, at suitable distances apart to prevent the salt from caking and break lumps that may have formed, as these wires operate in about the same manner as the parallel wires of a wire screen." With wavy wires "the salt can be very promptly reduced to fine particles even if caked in one mass".

Take two identical glass jars and punch the same holes in both lids. Under one lid, glue or solder three parallel lengths of stainless steel wire across the holes, a few millimetres below them. Fill both with table salt and leave them overnight, lids off, in a closed storage box with a bowl of warm water, to make the air damp. In the morning put the lids on. Shake each ten times over a bowl on a scale and weigh what comes out; repeat three times. Compare the two, and look at the lumps left inside.

**William Rogers** of Hartford, Connecticut, filed US 270,131 on 8 November 1882; it is dated 2 January 1883. **Honest limits.** The patent gives no sizes. The grain size and hole sizes are examples; the arching rule is a rule of thumb, and 75 % is the commonly quoted deliquescence humidity for sodium chloride at room temperature.