or concrete in a wet plastic or pliable form is employed between the surfaces of the adjacent bricks together and solidifies to bind the bricks together according to the present invention spacer elements are employed for dictating the spacing of the bricks apart one form of the spacer element being denoted generally by the numeral 20 another form of the spacer element being denoted generally by the numeral 30 and still a third form of the spacer element being denoted generally by the numeral 40 as best seen in fig2 the spacer element or apparatus 20 includes a flat open rectangular frame or base which is formed of a pair of longitudinally extending spaced parallel side struts 21 the ends of which are joined by spaced parallel straight transversely extending opposed end rods 22 also of equal length each of the struts 21 and 22 is cylindrical in shape being formed of plastic which is sufficiently rigid to maintain its shape and yet will flex when necessary at the four corners of the frame formed by the struts or rods 21 and 22 are pairs of oppositely protruding spacer fingers protrusions or prongs 23a and 23b each finger 23a or 23b is a conical member the proximal end of which is mounted integrally on the periphery of the struts 21 and 22 each pair of adjacent fingers 23a and 23b is provided with a common axis which is perpendicular to the axis of the struts 21 and 22 and intersect with these strut axes at the corners of the frame preferably each finger 23a or 23b is of approximately the.