GEOLOGY AND T01'0(;i{AriIV OF HAWAII. 93 



Geographic Position of the Islands. 



Considering the Hawaiian l.slands in relation to each other and to the rest 

 of the world, we find this wonderful group of mid-Paeifie islands to be made up 

 of twenty-one islands and a number of other small islets that are contiguous 

 to the shores of the larger ones. For the sake of convenience, the group, which 

 stretches for about 2,000 miles from southeast to northwest, has been divided 

 intd the leeward or northwest, and the windward or inhabited chain. In the 

 lei'ward islands are grouped eight low coral islands and reefs, and five of the 

 lowest of the high islands. Beginning at the western extremity, the low group 

 includes Ocean Island, ten feet high; Midway Island, fifty -seven feet high; 

 Gambler Shoal, Pearl and Hermes Reef, Lisiansky Island, fifty feet high ; 

 Laysan Island, forty feet high, and Maro and Dowsett Reefs. 



These are probably the tops of submerged mountains that have had their 

 summits brought up to or above the surface of the ocean by the combined 

 action of the hardy reef-building corals, the waves, and the transpdrting jxjwer 

 of the wind. The wind has had an important part in their final form, since it 

 has gathered up the dry sand left above the ordinary action of the wave and 

 piled it, as at Midway, in the center of a secure enclosure, formed by an encircling 

 coral reef, or as at Laysan, to form a sand rim about an elevated coral lagoon. 



Lying between the group of low islands and forming a connecting link 

 with the high or inhabited grouj), are five islands, the lowest of the high islands. 

 They fdnii a transition group lictwci'ii Ihc coral and the volcanic islands and a 

 second division of the leeward chain, .-ind are made up of Gardner Island, 170 

 feet high ; French Frigates Shoal, 120 feet high ; Necker Island, 300 feet higli ; 

 Frost Shoal, and Nihoa or Bird Island, 903 feet high. 



Together witli the low islands, they form the leeward chain of thirteen 

 islets, reefs and shoals that have a combined area of something over six square 

 miles, or about four thousand acres. With the exception of Midway, which is 

 the relay station for the Commercial Pacific Cable Company's wire across the 

 Pacific, they are uninhabited at the present time. The entire chain, with the 

 exception of Midway, has been set aside by the federal government to form the 

 Hawaiian Islands Bird Reservation, whicli, taken collectively, forms the largest 

 and most i)oi)u]ous bird colony in the world. 



To iiuuiy these remote, shimmering, uninhabited islands are devoid of inter- 

 est : to tlie naturalist, however, every square foot of the surface, and all tiie 

 life that inhabits them, has an interesting story to fell. The geologist finds 

 in them subjects of the greatest interest and importance. The thrilling 

 story of their up-building through centuries by the tireless activity of the 

 tiny animal, the coral polyp, that by nature is endowed with the mysterious 

 power of extracting certain elements in solution from the sea water and little 

 by little transforming them into n reef of solid lime-stone masonry, which, in 

 time. l)eeomes tlie foundation of inhaliilcd land is indeed most wonderful. 



