Which inventor patented principles related to gas turbines by the 1790s?
John Barber.
The development leading up to formalized internal combustion engines involved several distinct patents addressing different aspects of harnessing explosive energy. Around the 1790s, John Barber was an inventor who secured patents specifically covering the principles underlying gas turbines. Simultaneously, contemporaries like Robert Street were also advancing the field by patenting an internal combustion engine design that incorporated the use of liquid fuel, specifically petroleum, ignited by an external flame source, showing the concurrent exploration of various fuel and ignition methods.

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