that no demarcations are visible in the executed work. The sills, too, were graded by being made of the same clay, fired in the same kiln and at the same time as the brick, which they matched. The clay contained iron and the color was determined by the length of firing. The sill brick are 18ʹʹ long
and of special shape.
Another difficulty to overcome was the brick joint. A sample of wall was laid up, using common mortar which gave the appearance of grading the opposite way from the brick; that is, light at the bottom and dark at the top, manifestly an optical illusion.
As the brick grades from heather brown at the bottom to light buff at the coping, a separate specification was written for mortar for each story-unit. By having this color packed in numbered containers which could be mixed as the brickwork progressed, this diffi
culty was overcome. The mortar was otherwise mixed in the usual manner and the excess cost was slight.
For the decorative details terra cotta seemed the logical material in which to obtain the desired effects in brilliant colors. Pulsichrome or stippled finish, mat glaze to match the brick texture and high gloss to furnish contrast, and coin gold, baked in the terra