a name given to certain substances which shine in the dark without emitting heat. By this circumstance they are distinguished from the pyrophoroi, which, though they take fire on being exposed to the air, are yet entirely destitute of light before such exposure. Phosphori are divided into several kinds, known by the names of Bolognaian phosphorus, Mr. Canton's phosphorus, Baldwin's phosphorus, phosphorus of urine, and the like. The phosphorus of urine is by far the most remarkable, both with respect to the quantity of light which it emits, and its property of taking fire and burning very fiercely upon being slightly heated or rubbed.