[Note: my first post attempt gave me an error message, so I think it didn't go through as I don't see it showing up in the forum; apologies if this ends up duplicate and in that event please delete one copy.] The site I found this on is pretty crackpot, but I'm interested in debunking this particular article: http://www.21stcenturysciencetech.com/articles/spring01/Electrodynamics.html According to a more reliable source, http://math.ucr.edu/home/baez/physics/Relativity/SpeedOfLight/c.html "That continued until the 1870s, when Helmholtz discredited Weber's force law on the grounds of energy conservation, and Maxwell's more complete theory of propagating waves prevailed." However, from the first link: "The immediate topic is Helmholtz’s objection, that Weber’s Electrical Law could lead to the possibility of infinite work arising from a finite amount of work. Weber shows that for Helmholtz’s fears to be realized, electrical particles would have to move at enormous relative velocities, exceeding the constant c. He thus arrives at a concept of a limiting velocity, quite similar to that found 35 years later in the Special Theory of Relativity, yet arrived at by an entirely different process than that which leads Einstein to this assumption." Can someone comment on this? Even more audaciously, near the end he mentions another "accomplishment of Weber, the refutation of Clausius’ thermodynamics and the Helmholtz Energy Principle." Well, I see that the Smithsonian Libraries has the reference , but in the original German, and unlike some of the other Weber works, I can find neither a translation nor online version. Thanks in advance for anyone that can clear up my confusions with this.