The fewer and the lighter the weft threads are, the more flexible is the rug. The great depth of pile is also a good feature in certain rugs, as the heavier the fabric is the better it will lie. Stronger warp threads are usually put on each side to strengthen and give better support to the weft and sometimes both warp and weft are dyed, either in toto or at the ends only, in order to give a colored webbing to the finished product.
As a rule the nap of all rugs which are tied with the Ghiordes knot runs directly towards one end, while those that are tied with the Senna knot have a nap which runs towards one corner, right or left, according to whether the right or left Senna knot is employed. Frequently rugs are found with either the Ghiordes or the Senna knot where the nap runs directly towards one side. This may be due to an untwisting of the pile yarn or to the washing process, the washer in such cases having scraped the water out towards the side of the rug instead of towards the end.
[Illustration: KAZAK RUG PROPERTY OF MR. CHARLES SCHUBERT, CHICAGO, ILL.
PLATE LOANED BY THE SIMPLICITY CO., GRAND RAPIDS, MICH.
The field consists of a series of medallions in dark brown and green upon a field of old rose. The main border stripe is rather foreign to the rugs of this class, being more like those found in the Bergama products. The next two important stripes carry the "crab design" while all the four guard stripes carry the conventional "saw teeth." That this piece has some age is quite evident from the condition of its ends.
The soul of the Oriental is in his design, which is invariably well composed of skilfully conventionalized figures and superbly rich, harmonious colorings of which one never tires, while that of the European has a stiff set pattern which soon fails to attract.
The transmission of ancient patterns has been going on from century to century, the old designs and colorings being copied by the weavers from one generation to another and many of those used at the present time are doubtless the same that were used in the time of Abraham.
Each district, tribe or family had its characteristic patterns and color combinations which were regarded as its individual inheritance and were never copied by other districts, tribes or families. So it is possible for the expert to tell the locality from which an antique rug came, but the source of the modern one is not quite as accurately determined on account of the changes in designs brought about by the influence of immigration, travel and conquest. A design may be borrowed by a neighboring province and gradually undergo changes according to the taste of the adopting people until its original form is completely lost. The patterns have also become limited in number, so that to-day the entire output of Persian fabrics comprises only about thirty original designs, but of these the varieties of form, arrangement and combination are very large. Turkey and India have even, in some instances, adopted European designs. The Nomad products are perhaps the freest of all from outside influences.