Julian Wood's self-built triple transferator hot-air engine powers his canoe at Thames Traditional Boat Rally. 18th July 2009. Henley on Thames. Transferator engine is made from stainless steel food storage jars. Heat is supplied to engine from propane gas burner located below the hot-caps. One of two Stirling and hot-air engine powered boats taking part at the 32nd Thames Traditional Boat Rally, 2009.