108 NATURAL HISTORY OF HAWAII. 



the most favorable conditions. The late afternoon sun was lighting the bold 

 headlands and the fantastic f jord-lil^e valleys — in a way to accentuate every detail 

 of the singularly charming and beautiful panoramic view. The splendor of 

 Kalalau valley, the largest and perhaps the most wonderful of them all, — a val- 

 ley of grandeur, golden light, purple shadows, and sunset rainbows, — was a 

 welcome change after the daily monotony of the open sea on a long, lonely, 

 though happy voyage. 



The B.\eking S.vnds. 



Among the natural features of Kauai of considerable geologic interest 

 should be mentioned the barking sands of Mana. They consist of a series of 

 wind-blown sand hills, a half mile or more in length, along the shore at Nahili. 

 The bank is nearly sixty feet high and through the action of the wind the 

 mound is constantly advancing on the land. The front wall is quite steep. 

 The white sand, which is composed of coral, shells and particles of lava, has 

 tlie peculiar propert.\', when very dry, of emitting a sound when two handfuls 

 are clapped together, that, to the imaginative mind, seems to resemble the 

 barking of a dog. When a horse is rushed down the steep incline of the 

 mound a curious sound as of subterranean thunder is produced. The sound 

 varies with the degree of heat, the dryness of the sand and the amount of friction 

 employed; so that sounds varying from a faint rustle to a deep rumble may be 

 produced. Attempts at explaining this rare luitural phenomenon have left 

 much of the mystery still unsolved. However, the dry sand doubtless has 

 a resonant quality that is the basis of the peculiar manifestation, which dis- 

 appears when the sand is wet. That the barking sands are found in only a 

 couple of the driest localities in the group is also significant. Much of the shore- 

 line of Kauai, for example, is lined with old coral reefs that have partly dis- 

 integrated into sand that forms the beaches. This sand, as teolian deposits, is 

 often carried inland for considerable distances, and though composed of the same 

 material, it has none of the peculiar (pialities of the sand at IMana. 



Spouting 1 Iorn — C.wf.s. 



The blow hole, or spouting horn, is a familiar natural curiosity fairly com- 

 mon in the islands. Famous ones at Koloa, mentioned above, have long been 

 objects of interest to travelers. At half-tide, particularly during a heavy sea, 

 the larger ones throw- up fountains from openings five feet in diameter, that 

 often rise as a column of water and spray fifty or sixty feet in height. The 

 sound of the air as it rushes through the small crevices is most startling to the 

 spectator, who feels the rocks beneath his feet tremble as shrill shrieks and various 

 uncanny noises are produced by the wild rush of the water into the cave lielow 

 him. These caves are usually bubbles in the lava stream, or sometimes they 

 are formed by the washing away of the loose jjicces of rock underlying the more 

 solid outer crust of the old lava flow. 



The (■a\-es in the cliffs of llaeua are among Kauai's numerous places of 



