Original poster: "Jim Lux by way of Terry Fritz <twftesla-at-qwest-dot-net>" <jimlux-at-earthlink-dot-net> > > It is often erroneously stated (on TC websites!) that the Wheeler > formula is an empirical formula: As you can see, it is not. I've fixed my page at http://home.earthlink-dot-net/~jimlux/hv/wheeler.htm