Blow Pipe

 A blow pipe is a simple device consisting of a simple to complex tube. Air is forced through the tube by means of the lungs to forcefully add oxygen to a flame, increasing its heat. The flame could be produced by a simple oil lamp or gas-fed flame. This simple technique of rapid oxygenation can produce temperatures high enough to melt small amounts of goldalloys, and solders.

The first evidence of the use of a mouth blow pipe for alloying gold with silver and casting was in Ecuador and Peru circa 200 BC. This simple and successful technique is still used today.