Pyramid Frustum Small 320×315 Medium 640×631 Large 1024×1009 Download Tiff Original 2435×2400 | (378.9 KB) Description An illustration of a pyramid with the top cut off by a plane parallel to the base. The remaining part is called a frustum of a pyramid or a cone. Keywords frustum, part of pyramid, pyramid, rectangular base, shape, solid, volume Galleries Frusta Source: Claude Irwin Palmer Library of Practical Electricity: Practical Mathematics For Home Study (New York: McGraw-Hill Book Company, Inc., 1919) 215