368 



SCIENCE. 



[Vol. XIII. No. 327 



striking scenes at various points of the journey. Mr. Whittier has 

 written an introduction to the volume. 



— Ginn & Co. announce, in the Library of Anglo-Saxon Poetry 

 Vol. VL "Cynewulf's Elene," edited by Charles W.Kent, M.A. 

 The introduction of this work will contain an account of the manu- 

 script, author, sources, theme of poem, etc., as well as a discussion 

 of the versification, particularly of rhyme. The text is accompanied 

 by the Latin original at the foot of each page. The notes, in- 

 tended as aids to the student, will be full, and frequent reference 

 will be made to Cook's Sievers' " Grammar." 



— Mr. E. I. Brill of Leyden, Holland, announces the publication 

 of J. Biittikofer's work on " Liberia," founded on investigations 

 made in 1879-82 and 1886-87. At the present time, when the sup- 

 pression of African slave-trade attracts so much attention, a study 

 of the republic of Liberia will be very welcome to many readers, 

 and Americans will be particularly interested in it on account of 

 the enormous amount of labor and money devoted by our country- 

 men to the establishment and development of this republic. The 

 author, who has devoted much of his time to studies on the natural 

 history and ethnology of this country, gives a description of his 

 journey, and sketches of life in the republic, as well as among the 

 little-known aboriginal tribes. The illustrations are taken from 

 photographs and sketches made by the author. 



— Little, Brown, & Co. have now ready a volume entitled " The 

 United States," by Professor J. D. Whitney. The volume is made 

 up from the article written for the " Encyclopaedia Britannica," 

 modified in such a manner that it appears as originally written, 

 with the facts and figures illustrating the physical geography of 

 our country and its material resources, corrected down to the be- 

 ginning of the present year. They have also just issued the index 

 volume to the " Encyclopaedia Britannica," completing the work. 



— " Bell Hangers' Hand-Book," by F. B. Badt, is just the book 

 for those engaged in selling, installing, or handling electric bat- 

 teries, electric bells, elevator, house, or hotel annunciators, burglar 

 or fire alarms, electric gas-lighting apparatus, electric heat-regulat- 

 ing apparatus, etc. It is said to be the only book of the kind, and 

 is published by the Western Electric Company, Chicago. 



— E. & F. N. Spon will issue shortly, " Sewerage and Land 

 Drainage," by George E. Waring, jun., and announce as in press 

 ■" A Theoretical and Practical Treatise on the Strength of Beams 

 and Columns," in which the ultimate and the elastic limit strength 

 of beams and columns is computed from the ultimate and elastic 

 limit compressive and tensile strength of the materials, by means 

 of formulas deduced from the correct and new theory of the trans- 

 verse strength of materials, by R. H. Cousins. This firm further 

 announces a " Treatise on Water-Supply, Drainage, and Sanitary 

 Appliances of Residences : including Lifting Machinery, Lighting 

 and Cooking Apparatus, etc.," by Frederick Colyer ; and " The 

 Voltaic Accumulator ; an Elementary Treatise," by Emile Reynier, 

 translated from the French by J. A. Berly, C.E. 



LETTERS TO THE EDITOR. 



"* ^*Corresfionde»ts are requested to be as brie/ c 

 in all cases required as proof of good faiths 



The editor will be ^lad to publish any guerie 

 the journal. 



Tiventy copies o_f the number containing itis 

 ■free to any correspondent on reQuest. 



•ible. The writer's name is 

 onant with the character o_f 

 '.nnication zvill be furnished 



A New Mountain of the Bell. 



I HAVE just returned from a journey of four weeks in the Desert 

 of Mount Sinai, made with the especial object of studying the Jebel 

 Nagous in connection with the joint researches of Dr. Alexis A. 

 Julien and myself on musical sand. The " Mountain of the Bell " 

 is situated on the Gulf of Suez, about four hours and a half from Tor 

 by the roundabout camel-route. It was first described by Seetzen 

 in 1808, since which time it has been visited by Ehrenberg, Gray, 

 Wellstedt, RUppell, Ward, Newbold, and the late Professor Palmer, 

 as well as by large numbers of pilgrims. My observations confirm 

 in the main their accounts of the acoustic phenomena heard, but 

 my measurements differ widely from those of all the travellers save 

 Professor Palmer, 



The name " Jebel Nagous " is given by the Bedouins to a 



mountain, nearly three miles long and about 1,200 feet high, com- 

 posed of white sandstone bearing quartz pebbles and veins. On 

 the western and northern sides are several large banks of blown 

 sand inclined at high angles. The sand on one of these slopes at 

 the north-west end of the mountain has the property of yielding a 

 deep resonance when it slides down the incline either from the 

 force of the wind or by the action of man. This bank of sand I 

 distinguished from the others by calling it the " Bell Slope." It is 

 triangular in shape, and measures 260 feet across the base, 5 to 8 

 feet across the top, and is 391 feet long (high). It has the high in- 

 clination of 31" quite uniformly. It is bounded by vertical cliffs of 

 sandstone, and is broken towards the base by projecting rocks of 

 the same material. The sand is yellowish white, very fine, and 

 possesses at this inclination a curious mobility, which causes it to 

 flow, when disturbed, like molasses or soft pitch, the depression 

 formed being filled in from above and advancing upward at the 

 same time. The sand has none of the characteristics of sonorous 

 sand found on beaches. When pulled downwards by the hands, 

 or pushed with the feet, a strong vibration is felt, and a low note is 

 plainly heard resembling the deep bass of an organ-pipe. The 

 loudness and continuity of the note are related to the mass of sand 

 moved, but I think that those who compare it to distant thunder 

 exaggerate. The bordering rocky walls give a marked echo, which 

 may have the effect of magnifying and prolonging the sounds, but 

 which, as I afterwards ascerfained, is not essential. There are no 

 cavities for the sand to fall into, as erroneously reported. The 

 peak of Jebel Nagous rises above the Bell Slope to the height of 

 955 feet above the sea-level, as determined by a sensitive aneroid. 



After studying the locality and phenomenon for several days, 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 6 I 

 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 by camels from Suez. 

 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 and sand- 

 stone, and towards the west of 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 pro- 

 duce mobility (31"), it yielded the bass note, though not so loud as 

 on the Bell Slope of Jebel Nagous. In one 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. Th-e Nagous sand occurs at intervals 

 throughout the quarter-mile of low cliffs ; the main bank at the 

 east end being 1 50 feet wide and 60 feet high, measured on the 

 incline. I stirred up the 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 (S3°). 



I feel confident that this phenomenon is not very rare in the des- 

 ert, though the spontaneous production of sounds by sliding of the 

 sand without man's agency, 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 am informed that the peculiar re- 

 lations existing between England and Russia will prevent my visit- 

 ing norther.) Afghanistan at present. 



The Bedouins who accompanied us were greatly astounded at 

 my discovery of a new Nagous, and I fear that their faith in a 

 monastery hidden in the bowels of Jebel Nagous has received a se- 

 vere shock. 



It is interesting to note that the Nagous, or wooden gong, is in 

 daily use in the monastery of St. Catherine, Mount Sinai. I pho- 

 tographed Jebel Nagous and vicinity, as well as my new Nagous, 

 and collected specimens of the rocks, sand, etc. This is merely a 

 preliminary notice, fuller details being reserved for the work on 

 musical sand in preparation by Dr. Julien and myself. I shall be 



