NII-I0A OR BIRD ISLAND.
Our information about this island is derived from two reports made by Dr. S. E. Bishop in connection with a large excursion party from Honolulu, July 20-22, 1885. The Princess Liliuoka lani, afterwards the Queen, took the direction of affairs. The party numbered between two and three hundred people, including Dr. Bishop as surveyor and geologist, Hon. S. B. Dole ornithologist, James Williams photographer. Landing was effected with some difficulty and because the sea rose during the forenoon it was less easy to reembark in the small boats carrying the people and their effects to the steamer. The island was densely crowded with the nests of birds estimated to be 2,50o to the acre, which would make half a million nests and twice as many birds. Being disturbed by the visitors, the adult birds rose in enormous clouds, leaving their eggs and young, usually a single one in each nest. Survey ing was carried on industriously till all at once a fire broke out, and because the surface was covered with dry grass and twigs a dense smoke arose rendering it impossible to take observations, and everybody scrambled back to the steamer. The island is very like the rocks in other regions which furnish guano, and doubt less is capable of furnishing a considerable amount of fertilizing materials.
Though his observations were interrupted by the fire, Dr. Bis hop has described succinctly the main features of the geology and topography. He says: "The extreme length of Nihoa from W.N.W. to E.S.E. is not far from 5,200 feet. Its average width is about 2,000 feet, giving an area of about two hundred and fifty acres. Four-fifths of this
is a very steep grassy slope, the rest precipices. I did not see enough level ground to build a native hut upon without terracing. The general contours are much like those of Punchbowl towards Waikiki, save that the ridges tend inward instead of radiating out ward." The N.E. pinnacle, which overhangs, is eight hundred and sixty-nine feet high ; the higher N.W. pinnacle is nine hundred feet ; both subject to correction for from ten to twenty feet. As to the geology, Nihoa is the small remaining portion of an ex tremely eroded and deeply submerged volcanic dome homologous with the larger islands which still survive in their various stages of present upbuilding, recent extinction of volcanic activity, less or more advanced erosion, and slighter or deeper subsidence. Nihoa was probably a more ancient crater than Kauai. It seems to be a pair of clinkery pinnacles out of the inner core of a once mighty dome which has been eaten down by winds and rains for thousands of feet and during unreckoned ages.
Several parallel basaltic dikes cut the island from end to end and from summit to base, perhaps forty or fifty in number. Dr. Bishop infers from the great number of these dikes a very pro tracted period of igneous activity. The island may have been like Oahu or Maui originally, losing its substance partly by erosion and partly by submergence till only a small remnant is left.