GEOLOGY AND TOPOGRAPHY OF HAWAII. 97 



often found in these beds in a semi-fossilized stnte, pointing- to the wi\y in which 

 similar fossils have been embedded elsewhere in nnich older deposits. 



The rate of deposition of this valuable fertilizer is necessarily very slow and 

 is in direct proportion to the l)ird ]ioi)nlation. While it continues to be dc- 

 ])osited, the amount is small as the colony has been seriously intcrfciTcd with 

 owing to the slaughter of the greater number of the large al])atr()ss, w Inch doubt- 

 less have always been the chief factors in guano production in llicsc waters. 



^laro Reef was also the discovery of an American whaling ship in ]82(). It 

 is a rough quadrangular wreath of white breakers, about tliii'ty-tivc miles in 

 circumference, with no land in sight. 



Dowsett Reef is ])ut thirteen miles south of l\Iaro, and like it. is evidently 

 a young reef as compared with Laysan, since only a few rocks are awash here 

 and there above the breakers. It was named for Captain Dowsett of the whal- 

 ing brig "Kamehameha." whose vessel struck on the reef in 1872. 



Gardner and P^'rench Frigates Shoal. 



Coming next to the second division of the leeward chain, we tlnd. with tiie 

 possible exception of Frost Shoal, which is thirteen miles southwest of Xihoa, 

 that they are no longer wholly of coral formation. Gardner, the first of these 

 islands, is a cone-shaped rock 170 feet high by 600 feet or more in diameter. 

 There is a small island lying a short distance to the east of the main roek, but 

 deep water comes up close to the main island on all sides, and vertical sea clitfs, 

 sixty or seventy feet high, surround it on all sides. It vras discovered 1)\ an 

 American whaler in 1820, l)ut has seldom been visited since. This is the first 

 exposed evidence of volcanic rock to be met within the chain, and is of special 

 interest, since it is more than 700 miles east and south of Ocean Island, 

 and is at least 600 miles northwest of Honolulu. Such facts give the reader 

 an idea of the magnificent distances one encounters in traveling through the 

 length of the Hawaiian group. It also emphasizes the extent and magnitude 

 of the chain of volcanic mountains submerged in the central north Pacific, of 

 which, according to the legend of Pele's coming. ])reviously related, and the 

 opinion of learned geologists, only the tops of the tallest peaks are expostHl. 



The Fr(Mich Frigates Shoal- is about thirty s(|uai-e miles in exti'ut and 

 was discovered by the great navigator. La Perouse. in ITSii, ;ind by him named 

 for the two French frigates under his conunand. A striking \-olcanie i-ock, 

 120 feet high, rises from the lagoon, which is filled with growing reefs and shift- 

 ing sand-])anks. The surrounding reefs form a bai'i'iei- about the voleanii- imint 

 within and is perhai)s the b(\st example of this form (tf" i-eef in tlie lirou]). 



Necker Island. 



Necker Island was discovered in 17S(i. duriiiL; the snme expedition that 

 ni;ide the French Frigates Shoal first known to the world. It was named by 

 the discoverer for the ureat French statesman and financier who convened the 



- Not Frigate as usually written. 



