BRIMSTONE, the popular name of sulphur (q.v.), particularly of the commercial "roll sulphur." The word means literally "burning stone"; the first part being formed from the stem of the Mid. Eng. brennen, to burn. Earlier forms of the word are brenstone, bernstone, brynstone, etc.
Note - this article incorporates content from Encyclopaedia Britannica, Eleventh Edition, (1910-1911)