The modifications in architecture brought about by the difference in direction of these cleavage planes are apparent. The ancient builders in the Navaho Monument region utilized the vertical faces as supports for walls of rooms on one or more sides. In some cases the face of the cliff forms the rear walls; in others a side wall and the rear wall of a room are formed by vertical cleavage planes at right angles, as shown in plate 9. It can be seen that adjacent houses built upon fallen rocks of different heights, the vertical faces being utilized as rear walls, would seem to stand one above another, or, in other words, they would present the well-known terrace form which exists in some modern pueblos. The writer approached this ruin by following the fallen débris at the end, where the rooms, being without covering and exposed to the elements, are most dilapidated. Over this fallen mass one makes his way with difficulty and is often in danger of falling from the cliff. On account of the perpendicular face of the cliff below the foundations of the other end of the ruin, it is impossible to climb into it, except from this side. On approaching the ruin there is to be seen on the vertical face of the cliff a pictograph (pl. 12) worthy of special mention, or rather two pictographs which are doubtless connected in meaning. The larger of these is a circle, painted white, resembling a shield (a common object in pictographic representation), the other a horned animal, perhaps a mountain sheep.[29] The figure on the shield, which bears evidence of former coloration, represents a human being with outstretched arms, the hands being raised to the level of the head. On each side of the body are represented two designs—a circle of yellow and a crescent in which are parallel bands of red, yellow, and probably green. The rooms in this cliff-house are rectangular, cubical, or box-like structures built against the face of the cliff, which serves as their rear wall. There are no towers or round rooms such as those that lend picturesqueness to several of the Mesa Verde cliff-dwellings. Few of the rooms are more than two stories high, the appearance of terraced rooms being given by the varying heights of their foundations. The masonry is crude, the lines are irregular, and the external faces of the walls vertical. The interior wall was probably plastered, and some walls afford good evidence that their exterior was formerly covered with mud. A marked feature of ruins in this region is the adobe walls supported by rows of stakes with interwoven sticks. No adobe bricks were seen in the walls examined.[30] [Illustration: BUREAU OF AMERICAN ETHNOLOGY BULLETIN 50 PLATE 9 BETATAKIN—WESTERN END] [Illustration: BUREAU OF AMERICAN ETHNOLOGY BULLETIN 50 PLATE 10 GROUND PLAN OF THE BETATA KIN NAVAHO IND·RES·ARIZ· BY W·B·DOUGLASS U·S·EXAMINER OF SURVEYS ·GENERAL LAND OFF· ]