530 ANNUAL REPORT SMITHSONIAN INSTITUTION, 19 63 



excellent view of the surrounding terrain, and for this reason they 

 were commonly used as sites of watchtowers and forts of recent date. 

 Others, which do not offer a commanding view, were presumably used 

 because of the presence of raw material, their more sheltered locations, 

 and possibly other advantages, such as availability of water, which 

 cannot be assessed today. Often spurs are found in close proximity 

 to other spurs and outliers, suggesting the possibility that these fea- 

 tures are remnants of what was once a large continuous surface which 

 held a greater spread of artifacts. If this is the case, these artifact 

 concentrations may not represent isolated campsites. 



Sites on low-lying features (fig. 2-F). — These sites, which are often 

 no more than 10 or 15 meters above wadi level, occur on top of mounds 

 and spurs of Cretaceous sediments, on abandoned portions of alluvial 

 fans, and on rubble and gravel spreads (pi. 3:1). These surfaces 

 presumably had not yet come into existence when people were leav- 

 ing artifacts about on the plateau, benches, spurs, and outliers. The 

 darkly patinated artifacts characteristic of sites on the latter fea- 

 tures rarely occur on these low-lying surfaces. Until there has been 

 time to study this material, little can be said about it except that it is 

 only slightly or not at all patinated. In certain situations where arti- 

 facts are subject to occasional inundation, this patination is thin and 

 white. The average artifact size is much smaller than that of the 

 higher-lying material, and typologically late implements — tanged pro- 

 jectile points, bifacial foliate (leaf -shaped) points, etc. — sometimes oc- 

 cur in these contexts. It is possible that analysis will permit this ma- 

 terial to be referred to two industries : The one just mentioned which 

 sometimes approaches microlithic proportions, and a second, interest- 

 ingly enough, which is often associated with pre-Islamic and perhaps 

 even preceramic architectural features. This might be described as 

 a crude, nondescript flake industry, generally of rather small average 

 flake size. Unpatinated or slightly patinated artifacts were, in sev- 

 eral cases, found in and about curious stone structures, often without 

 ceramic associations. These structures were most commonly stone 

 circles, although rectangular alignments of stone, and complexes of 

 circles, or of circles and rectangles also occur. As these stone struc- 

 tures are commonly found on the low-lying rubble and gravel spreads 

 where artifacts of this kind are apt to occur, it is possible that the 

 association is fortuitous. 



Roch shelters (fig. 2-G) . — Large fall blocks from the limestone cliffs 

 are strewn about on the lower slopes and on the gravel and rubble 

 spreads (pi. 3:2). Some of the more favorably situated blocks are 

 used today by Bedouin as shelters, and are the primary source of pre- 

 Islamic South Arabic graffiti and rock paintings. In a few instances, 

 flaked stone artifacts were found around the shelters in sufficient 

 quantity to suggest that they are associated with occupation. Judging 



