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Show SAND THAT BARKS. Account of the Wonderful Musical Earth of the Famous Sandwich Sand-wich Islands. CUBIOUS POETION OF THE GLOBE. asioal Sand is Found in Several CountriesSome Coun-triesSome Hypotheses to Explain. Tbeeo-called "barking sands" of Kauai re mentioned in the works of several rayelers in the Hawaiian islands, and 3ve worldwide fame as a natural curi-ity curi-ity As a rule, however, the printed ao-nuutsare ao-nuutsare meager in details, and show ie authors to have been unacquainted ith similar phenomena elsewhere. Jointly with Dr. Alexis A. Julien, of ;0!umbia college, New York, I have been hidying the properties of sonorous sand 3r a long time, and have visited many realities in America, Europe and Asia; ence I was able during a recent visit to :anai to make some notes and compari-,ns compari-,ns that may interest the reeidente of iit kingdom. Notwithstanding recent rains I found ie sand on the dune at Mana dry to the epth of four or five inches, and when nshed down the steep incline it gave at a deep base note having a tremulous mracter. This hardly resembles the harking" of a dog, but a sound some-ht some-ht like it is produced by plunging the ands into the sand and bringing them porously together. Another way is to 11 a long bag three-quarters full of sund, nd then dividing its contents into two irts, holding one in each hand, to clap ie two portions together. This I had land to bo a good method for testing ;e sonorousness of sand on sea beaches. bag of the sand will preserve its oustic qualities a long time if kept dry id not too frequently manipulated, he angle at which the sand lies where falls over the dune is 81 degrees; the raoronsness extends several hundred at along the dune, being interrupted r a creeping vine that thrives marvel-nsly marvel-nsly in snch a soil. A similar dune of sonorous sand oo-irs oo-irs on Xiibau, as has long been known i residents of the island, and it has been so reported to occur near Eoloe. Tbese observations, simple as they are, lire been of special interest to me, be-mse be-mse they show that the sand of these icalities forms a link between that of ie sea beaches and that of a certain hill i the Gulf of Suez known as Jebel Nanus, Na-nus, and which I visited in April, 1889. aaorous sand is of more common occur-nce occur-nce than generally supposed. It is and on the Atlantio coast of the Unit-! Unit-! States from Maine to Florida, on the urific coast, in Europe, Japan, Africa, asmania, etc., as well as on the shores of any fresh water lakes. In these localities forms areas generally between' low le and the base of adjoining dunes, and aits sounds only when subjected to iction by the feet and hands or in a ig as described. At Jebel Nagous, in rabia, on the other hand, the sand rests i a ravine, and produces sound only hen it rolls down the incline (which it ten does spontaneously) and fails to re-ond re-ond to kicks and cuffs. The sand at Mana, as shown, unites in j self both these acoustic properties. The igle at which the sand lies at Jebel agons is the same as at Mana, 31 de- . ees being the "angle of rest" for fine ' 7 sand. The musical notes obtained j these far separated localities are also i ie same, but in Arabia the incline is W feet high, and consequently tha mnds are far louder, especially as they further magnified by being echoed 'itn adjoining cliffs. The sand at Kauai and Niihau is made of fragments of shell and coral, while at of all other localities known to us l er 100 in number) is siliceous. This lows that the sonorousness is inde- j mdent of material. Examination under ie microscope further shows that the wous quality is not connected with e shape of the grain. Sonorous sand is distinguished by 'ing free from fine dust or silt; the in-ndnal in-ndnal grains are very uniform in size. is very easy to deprive sand of its rustic power by mixing a little earth th it or by wetting it. It is difficult, not impossible, to restore to sand its norons quality when once "killed." A number of hypotheses have been "Psed to explain the cause of this cu-us cu-us property of certain sands. The evalent idea in these islands that the iand is due to the cellular structure of e sand must be abandoned, since most nwons sand is not so constituted, that Kauai forming an exception. Some lfe attributed the sonorous quality to "ne crusts, others to electricity, effer-scence effer-scence of air between the .particles, erberation within subterranean cv-iss cv-iss and to solarization, and one author npts to explain the phenomena by "ting of "a reduplication of impulses Ijtog air in vibration in a focus of These theories Dr. Julien and I reject reasons I cannot here detail, and we eve the true cause of sonorousness to ' connected with thin pellicles or films sir or of gases thence derived, depos- and condensed upon the surface of 19 6ani grains during gradual evapora-"a evapora-"a fter wetting by seas, lakes or rains. virtue of these films the sand grains :Cme separated by elastic cushions of sensed gases, capable of considerable 'ration, whose thickness we have ap-aunately ap-aunately determined. The extent of ? vibration and the volume and pitch j e soUn(j produced we also find to be ;Sely dependent upon the forms, struct- ! es anii surfaces of the sand grains, and ' anally upon their purity or freedom f? fine silt or dust. e have shown that the pitch of the rasical notes obtained on sea beaches is Portional to the mass of sand moved n let the maa8 019 lower t tone8-'u tone8-'u ?nesof Kauai and Niihau the ;e holdstrue.-H. Carringtcra Bolton, sjj ln Honolulu Commercial Adver- |