div. 10, 20, 30, 40, 50, 60 parts to the inch.

Keuffel 8» Esser Co.. New York.

Chapter 42 THREE-DIMENSIONAL METHODS

EY MEANS of three-dimensional models, similar to those shown in 354, 355A, and 355B, it is possible to present three variables in the form of curves rather than the usual two. Other methods of showing three dimensions are illustrated in the isometric block diagram in 356A and in the trilinear chart in 359B.

Commonwrallh Edison Company. Chicago. Ill SCALE .6

Three-Dimensional Curve of the 1935 Load of the Commonwealth Edison Company.

1. Thrcc-ply bass wood was used in the construction of this three-dimensional model.

Each curve is a board which, before it was cut. measured Yt x 17 x 11 inches.

2. The Klass case is ruled with a scale of kilowatts on the sides and with the 24-hour

period from midnight to 12 midnight on each end. The third dimension is by days, the scale for which is on the base.

3. The exhibit is about 5 feet long and weighs approximately 300 pounds.

THREE-DIMENSIONAL METHODS

Pacific Gas and EIrctric Company, San Franrlsco. California. A. Three-Dimensional Curve of the 1935 Load of the Consolidated System of the Pacific Gas and Electric Connpany.

1. Dimensions of the model, excluding base, are 12" x 24" x 12" high.

2. The front black section represents a load curve showing variation from day to day

throughout the year for the last half hour of each day. The clefts between the tifty-two sections are Sundays. Additional clefts are the holidays.