more labor, hence the plan of molding vase upside down as illustrated.

The centering of your patterns may be accomplished by using a cover board that is absolutely square, in the center of same bore a 14" hole, if the pattern is circular—if a square pattern bore two of these holes, into same place iron rods which go through 14" holes in the pattern, and so hold the pattern exactly in the center of the cover board or modeling board. The placing of flask can be guided by placing upon this board and then by measurements securing the exact point it must rest, to have the space between pattern and flask equal at every side; small blocks of wood may then be nailed to the cover board, on the outside of flask, as guides so that the flask, or any other flask of the same size, will set exactly in the same place. By using this cover board for all sections you thus mold the various sections of pattern in the sand, so that they go together exactly, as perfect as if pattern was in one piece.

The work to which this method of combin

ing molds may be applied is unlimited, as it lends itself to every style of large work, no matter what the size, with perfect and exact results, thus enabling the worker to produce monolithic pieces of work that heretofore he judged could only be produced in separate units and then built up.

The molding of a column with base and capital attached is easily accomplished; this may be done either by having the pattern in sections, as shown for the lawn vase, and then combining the sections to make the entire mold, or dividing the column into halves as well as base and capital, which can be attached to the two sections of column. For the latter way a flask is built that is about 6′′ wider than the greatest diameter of the pattern and as much longer than the greatest length of the complete pattern; then the mold is made in the usual manner by laying pattern in bottom of flask and filling in with sand, reversing the mold, making the parting and then placing the other half of pattern upon the first half with the cope of flask around same and finishing the mold; the gate

or inlet is provided at one end and the concrete poured from that end. This enables a complete column to be molded, from the use of any of the wood columns, divided in halves, and employed as a pattern, or the metal division plates cut in outline of pattern may be employed when it is desired not to divide the column.

In building up the sand molds in sections for a round column the base may be a clay model, made with template, as well as the shaft and capital and the sections set upon each other to make a perfect and complete mold. With the square column the pattern can easily be built of wood forms ornamented with the usual mouldings cut with miter joints, so to fit perfectly around the surface of pattern; the sections must be so arranged as to permit the easy removal of pattern from the sand mold without disturbing the sand mixture.

The sand mold has the advantage that it can mold any article with as much ornamentation or under-cutting as any mold, and even far more than the average metal or plaster molds

permit; for the sand mold is easily taken apart or broken into small particles to release the work-this is something not possible with any other style of mold; hence the only limit to the shape or degree of ornamentation to work cast in a sand mold, is the removal of the pattern from the mold, and in the case of a clay model this can be removed in pieces, if only one cast is desired, hence the sand mold easily and successfully accomplishes what is impossible with any other system of molding ornamental concrete, known to the concrete worker to-day.

CHAPTER X

MAKING ROCK EFFECTS WITH SAND MOLDS

THE ornamenting of concrete work with rock face effects is desirable for many purposes and is easily accomplished with sand molds in two different ways; the method shown at (a) in Fig. 8, employs a face plate made from the sand mixture in the same manner as the impression is taken from a pattern, and gives a sand mold that can be employed for many

purposes.

The cover board is placed under the flask and this is covered with spalls or pieces of broken stone; these must be laid with care, tightly together, so to form the outline of broken rock that you wish to imitate and then by placing the sand mixture upon this and tamping down, you make a mold that will cast an exact fac-simile of the face of the broken stone, laid in the bottom of flask.