Inventor of first working Internal Combustion Engines

According to an article in the current *Photo Techniques Magazine * (Vol. 26/#6 or November/December 2005), Joseph and Claude Niepce invented and built the first internal combustion engine. They began working on it in 1797 and were granted a patent, signed by Napoleon in 1807. To prove their work, they built and installed the engine on a small boat and test drove it on the Saone River. (In case your wondering why this article appears in the above stated magazine, it’s because Joseph Nicephore Niepce is also credited with taking the oldest surviving photograph predating BTW daguerreotypes).This claim is also supported at this site (sorry to keep deviating but the UT currently has Niepce’s photograph at the Harry Ransom Center).

According to this site, they list the inventor of the Internal Combustion Engine as J.J. Etienne Lenoir in 1859. I found this by googling on exact phrase “Internal Combustion Engine” and also using keyword “inventor”. This google search does not readily identify Niepce’s name at all (at least searching the first 50 or so listings).

Just to avoid the possible confusion, Christian Huygen’s design for an internal combustion engine ~1680 used gunpowder but he nor anyone else was ever able to successfully construct such an engine.

So I ask - Who did in fact invent the internal combustion engine and why is there conflicting information?

(Please forgive my lack of accent marks on the names as I do not know how to properly enter them using the message box)

A cheap ploy to bring this back up on everyones “New Posts” listings.

Check out this link: http://inventors.about.com/library/weekly/aacarsgasa.htm

Thanks for the link and from it I got the following listing (Huygen’s engine is listed the same as my reference):

1807 - Francois Isaac de Rivaz of Switzerland invented an internal combustion engine that used a mixture of hydrogen and oxygen for fuel. Rivaz designed a car for his engine - the first internal combustion powered automobile. However, his was a very unsuccessful design.

What I still don’t understand is what are the distinctions between de Rivaz’s and Niepce’s engines? I don’t have a reference for what fueled Niepce’s engine and Rivaz’s hydrogen and oxygen would not have been practical fuels thus the later emphasis was on maximizing efficiency and fuels leading to the four-cycle gasoline powered engine.

Anyone out there offer any help?