[Drawn for this work by L. W. Truesdell, Tinman, Owego, N. Y.] Original.

FIG. 15.

From a point C as a centre, describe a circle AB equal to the large circumference; with the point F as a centre, the depth of the vessel, describe a circle DE equal to the small circumference; then draw the lines GH and RS tangent to the circles AB and DE; from the point of intersection 0 as a centre, describe the arcs ACB and DFE; then ADEB will be the size of the vessel, and three such pieces will bo an envelope for it, and AJBTFU the altitude; then by dividing the sector SOH into sections AB, DE, PQ, and WX, you will have a set of patterns for a pyramid cake; and the sector AOB will be one-third of an envelope for a cone.

In allowing for locks, you must draw the lines parallel to the radii, as represented in the diagram by dotted lines, which will bring the vessel true across the top and bottom.