Sodium
This is a very widely diffused and abundant element. As chloride, it occurs in rock-salt, sea-water, salt-springs, and many mineral waters; and as silicate, in many minerals. Metallic sodium was first discovered by Sir Humphry Davy. It is prepared in the same manner as potassium, requires the same measures for its preservation, and exhibits properties similar to those of that metal. See POTASSIUM; SALT; SODA; FLUID ALLOY.