The rivalry between James Watt & Trevithick about high pressure vs. low pressure steam always remind me of the same rivalry between Nikola Tesla & Thomas Edison about AC vs. DC current. The two successful businessmen Edison & Watt won the battle during their lifetimes, and the two financial losers Tesla & Trevithik ended up winning the respect of the world forever; not to undermine all the other great innovations Edison & Watt did during their lives.