This section is from the book "Cyclopedia Of Architecture, Carpentry, And Building", by James C. et al. Also available from Amazon: Cyclopedia Of Architecture, Carpentry And Building.
A barrel of Portland cement will contain 370 to 380 pounds, net, of cement. Its capacity averages about 3.3 cubic feet, although with some brands the capacity may reach 3.75. The expansion when the cement is thrown loosely in a pile or into a measuring box, varies from 10 to 40 per cent. The subject will be discussed further under the head of "Concrete."