1889. | NEW YORK ACADEMY OF SCIENCES. 183 
I formed the opinion that it could not be unique,’as hitherto sup- 
posed; and accordingly I tested every steep slope of blown sand 
met with on the caravan route northward to Suez. On April 6th, 
j examined a steep sand-bank on a hillock only 45 feet high, and 
was rewarded by the discovery of a second Nagous. This new 
Nagous is in the Wadi Werdan, only five minutes off the regular 
caravan route, and one and a half days from Suez by camels. 
The hillock is called by the Bedouins Ramadan, and forms the 
eastern end of a range of low hills about one-quarter of a mile 
long; being the only hills in the Wadi, the locality can easily be 
found by travellers. The hills consist of conglomerate, sand- 
stone, and gypsum; they slope up gradually from the north and 
end in bold cliffs on the south side. Sand blown by the north 
wind is carried over the cliffs and rests on the steep face at two 
inclinations, 31° above and 21° or less below. By applying the 
usual tests with the hands to the fine-grained sand, I found that 
wherever it lies at the requisite angle to produce mobility (31° 
it yielded the bass note, though not so loud as on the Bell Slope 
of Jebel Nagous. Inone instance, my friend and fellow-traveller, 
Henry A. Sim, Esq., of the Madras Civil Service, who kindly 
aided me in my investigations, heard the sound while standing 
100 feet distant. 
The Nagous-sand occurs at intervals throughout the 500 yards 
of low cliffs; the main bank at the east end being 150 feet wide 
and 60 feet high, measured on the incline. I stirred up the 
mobile sand pretty thoroughly on this slope, and the next day it 
failed to give the sounds, not having recovered its properties. 
The intervening night was very cold (53° F.). 
I feel confident that this phenomenon is not very rare in the 
desert, though the spontaneous production of sounds by sliding 
of the sand, as at Jebel Nagous, may be. 
Whether the Rig-i-Rawan, north of Cabul, is caused by similar 
conditions, remains to be determined; but I fear that the pecu- 
liar relations existing between England and Russia will prevent 
my visiting northern Afghanistan. 
Our dragoman, Hanna Abusab, and the Bedouins who accom- 
panied us, were greatly astounded at my discovery of a new 
Nagous; and the faith of the latter in a monastery hidden in the 
heart of Jebel Nagous has received a severe shock. It is inter- 
esting to note that the Nagous, or wooden gong, is in daily use at 
the monastery of St. Catherine, Mt. Sinai. 
I made photographs of Jebel Nagous and vicinity, as well as 
of the new Nagous, and collected specimens of the rocks, sand, 
etc. This communication must be regarded as a preliminary 
notice, full details being reserved for another paper. 
I shall be obliged if those who have opportunities of examining 
