GEOLOGY AND TOPOGRAPHY OF HAWAII. 101 



from which to study, in some detail, the main geouraphic. topographic and 

 geohjgic featui-cs of the group. 



NlIHAU. 



To the northwest of Honolulu lie the islands of Xiihau and Kauai. The 

 former, the farther removed of the two, is in a northwesterly direction 

 from Honolulu and is in line with the islands mentioned in another chapter as 

 forming the leeward chain. It is seventeen miles west of Kauai from which it is 

 separated by a very deep ocean channel. It is about eighteen miles long by 

 eight miles in width, at the widest part, and has an area of ninety-seven square 

 miles. The highest portion attains an elevation of about 1300 feet above sea 

 level. 



The island consists of a high central section called Kaeo, surrounded by a 

 plain on three sides. On the north and west sides it is the highest and it is here 

 that steep clitfs occur where the high land joins the summit flat. The higher 

 part is irregular and of a basaltic origin, but is without the sharp peaks that 

 characterize some of the larger islands. A large, natural pond near the center 

 of the island and several smaller ponds and artificial reservoirs are found in 

 various sections. 



While Niihau shows evidence of great erosion it is evident that its moderate 

 height and small size has prevented it receiving the abundant rainfall which 

 has been an important factor in aging its larger companions. 



A large part of the island is low, apparently of coral or leolian origin, 

 and is the inliabited section. The island is now utilized as a great sheep ranch, 

 there being extensive areas of grass land, especially suited to grazing. Per- 

 haps 150 natives, mostly comparatively new arrivals, now inhabit the island, 

 and together with the old inhabitants, all told, are but a remnant of the 

 thousand sturdy Hawaiians who made it their home less than seventy years 

 ago. The island is noted in the group as the one on which is found the famous 

 sedge from which the natives weave their serviceable soft grass mats, although 

 the same plant occurs in suitable localities on all of the islands. The beaches 

 are strewn with beautiful, though small, sea shells, known as Xiihau shells,i 

 which are strung into long necklaces called Niihau leis. 



Near Niihau are two cinder cones, Kaula on the west and Lehua on the 

 northeast, which form small detached islands. Prof. Hitchcock says, "The first 

 is about the size and shape of Punchbowl, cut in two and the lower half destroyed 

 by the waves. The concentric structure of the yellow cinders, much like ttie 

 lower surface of Koko Head, is very obvious. Lehua appears to be a similar 

 remnant, less eroded, as it has maintained about 200 degrees of its cir- 

 cumference instead of the 1-10 degrees of Kaula. Both these crater cones have 

 the western or leeward side the highest, because the trade winds drive the 

 falling rain of ashes and lapilli in the direction of the air movement, building 

 up a compact laminated pile of nuiterial to leeward. The subsequent erosion 



