Yes. Granville's most original contribution to the business of stock speculation is On Balance Volume. It was a simple yet brilliant way of charting price and volume moves as one dynamic.

Rather than go into it any more myself, here is a little exposition about OBV on Investopedia.

http://www.investopedia.com/terms/o/...

Granville got a lot more complicated in his number theories later on, after the invention of OBV. Also, his own ego led him into making predictions and then sticking with them at the wrong times, ie, fighting the tape. That does not, in my view, take anything away from his contribution.

Michael