abian Nesnas or _Empusa_. Nicolo Conti in the
Chaldaean desert is aroused at midnight by a great noise, and sees a vast
multitude pass by. The merchants tell him that these are demons who are in
the habit of traversing the deserts. (_Schmidt's San. Setzen_, p. 352; _V.
et V. de H. T._ 23, 28, 289; _Pliny_, VII. 2; _Philostratus_, Bk. II. ch.
iv.; _Prairies d'Or_, III. 315, 324; _Beale's Fahian_; _Campbell's Popular
Tales of the W. Highlands_, IV. 326; _I. B._ IV. 382; _Elphinstone_, I.
291; _Chodzko's Pop. Poetry of Persia_, p. 48; _Conti_, p. 4; _Forsyth, J.
R. G. S._ XLVII. 1877, p. 4.)

The sound of musical instruments, chiefly of drums, is a phenomenon of
another class, and is really produced in certain situations among
sandhills when the sand is disturbed. [See supra.] A very striking account
of a phenomenon of this kind regarded as supernatural is given by Friar
Odoric, whose experience I fancy I have traced to the _Reg Ruwan_ or
"Flowing Sand" north of Kabul. Besides this celebrated example, which has
been described also by the Emperor Baber, I have noted that equally
well-known one of the _Jibal Nakus_, or "Hill of the Bell," in the Sinai
Desert; Wadi Hamade, in the vicinity of the same Desert; the
_Jibal-ul-Thabul_, or "Hill of the Drums," between Medina and Mecca; one on
the Island of Eigg, in the Hebrides, discovered by Hugh Miller; one among
the Medanos or Sandhills of Arequipa, described to me by Mr. C. Markham;
the Bramador or rumbling mountain of Tarapaca; one in hills between the
Ulba and the Irtish, in the vicinity of the Altai, called the Almanac
Hills, because the sounds are supposed to prognosticate weather-changes;
and a remarkable example near Kolberg on the shore of Pomerania. A Chinese
narrative of the 10th century mentions the phenomenon as known near
Kwachau, on the eastern border of the Lop Desert, under the name of the
"Singing Sands"; and Sir F. Goldsmid has recently made us acquainted with a
second _Reg Ruwan_, on a hill near the Perso-Afghan frontier, a little to
the north of Sistan. The place is frequented in pilgrimage. (See _Cathay_,
pp. ccxliv. 156, 398; _Ritter_, II. 204; _Aus der Natur_, Leipzig, No. 47
[of 1868], p. 752; _Remusat, H. de Khotan_, p. 74; _Proc. R. G. S._ XVII.
91.)

NOTE 3.--[We learn from Joseph Martin, quoted by Grenard, p. 170 (who met
this unfortunate French traveller at Khotan, on his way from Peking to
Marghelan, where he died), that from Shachau to Abdal, on th