Note 223 — No. XXIV.

Ver. 88. Sulphur—A substance which, when cold, reflects the yellow rays, and is therefore said to be yellow. When raised to a temperature at which it attracts oxygene (a process usually called burning), it emits a blue flame. This may be beautifully exemplified, and at a moderate expense, by igniting those fasciculi of brimstone matches, frequently sold (so frequently, indeed, as to form one of the London cries) by women of an advanced age, in this metropolis. They will be found to yield an azure, or blue light.