Helmholtz,On the Sensations of tone.

Hi,
I was on Amazon's web site looking up Helmholtz' On the Sensations of
Tone' ($ 12.76) and found they didn't have much info there about it.Their
page says "Publication date: December 1954".Is there more than one
edition of this book around or is this the same one,@570
pages,translated,with additions,by Alexander Ellis ? Also would this be a
"if you can only buy one book,this is it " category book ? Any other
suggestions ?
I'd like to get Sethares' book,but $69.95.....

-Drew