A traditional British unit of volume used mostly for dry commodities. A coomb is 4 Imperial bushels; this is equivalent to 5.1374 cubic feet or about 145.48 liters
Russ Rowlett (Director), How Many? A Dictionary of Units of Measurement, Center for Mathematics and Science Education University of North Carolina, USA 2005. http://www.unc.edu/~rowlett/units/dictA.html, (Unit of Meas and Covr Factors - Amer) {608}