Blow-Pipe, in chemistry and mineralogy, an instrument by which the breath may be directed in a stream upon the flame of a lamp, or candle, in order to vitrify a small quantity of mineral substance. The process of assaying in the dry way, may readily be performed in the same manner.

Most of the experiments which can be made by means of a large apparatus, may also be accomplished by the blow-pipe, in a much shorter space of time, while even the smallest particle of the matter is sufficient. "The first inquiry to be made, " says M. Bergmann, is, what a substance contains, not how much." Experiments with the blow-pipe have this advantage over those conducted in crucibles, that we can distinctly see all the phenomena from beginning to end; by which means we obtain an illustration of the series of operations and their causes.