[bhzvflzm] isomorphism between horizontal and vertical brick tessellations

consider a 2x1 brick (rectangle of width 2 and height 1) with a U and an upside-down U printed on it: [∪∩].  each symbol occupies half the brick.

arrange the bricks in the standard bricklayers' pattern, each horizontal row offset by half a brick width from the row beneath.  the U's and upside-down U's of adjacent rows will seem to meet, enclosing 1x2 ovals, paradoxically creating a vertically oriented bricklayers' pattern.