FRESH-WATER SPRINGS IN THE OCEAN. 679 



gallon is less than sixty. At Molokai, where the salinity is greater, it 

 is stated that the cane is not affected unless the number of grains per 

 gallon exceeds one hundred. 



From all the facts available, the conclusion seems warranted that 

 the underground waters descend to the seas from the highlands and 

 remain free from admixture till the pressure of the ocean exceeds that 

 of the descending stream, when a commingling of the two liquids 

 results. When the ocean pressure becomes greater, because of exces- 

 sive pumping, the brine will increase in amount. In a small island 

 the ocean water will force itself inland quite conspicuously. Molokai 

 illustrates this proposition. Our information is derived from a report 

 of Waldemar Lindgren in the Water Supply and Irrigation Papers 

 No. 77. The springs there are of three classes, of which only the first 

 calls for consideration here, (1) those very near the shore, (2) those 

 breaking forth up to the height of 2,000 feet, (3) running streams still 

 higher. 



Shallow wells near the shore show the following degrees of salinity 

 or number of grains per gallon, 238, 403, 150, 126, 109, 86, 102, 86 ; 

 of deeper wells the first gave 86 grains at the surface and became 

 ocean water at 50 feet. The second became ocean water at 125 feet. 

 At Naiwa there are 90 grains of salinity at 70 feet. At Kalamaula 

 several deep wells gave 102 and 101 grains and pure ocean water. 

 The American Sugar Company sank several deep wells at Kaunakakai, 

 of which the first five had 150 grains per gallon; others ranged from 

 270 to 4-85 grains. The Eisdon wells yielded 70 to 79 grains per 

 gallon. Better results appeared in nine wells sunk at Kawela, many 

 of them showing less than 50 grains of salinity. The fresh water is 

 contaminated up to four or five feet above the sea level. None of the 

 underground streams can be more than eight miles in length, and many 

 do not exceed three. It is also probable that no impervious layer pro- 

 tects the underground water as in Oahu. 



6. There are springs of fresh water near the sea-shore in Oahu 

 which may correspond to the artesian fountains. One is the famous 

 Kamehameha Bath near Punahou, a second is near the railroad station 

 at Honolulu, and a third gladdens the thirsty soul at Waialua near 

 the Haleiwa Hotel. Another is at Niu, west of Koko Head. • It would 

 seem that the underground water finds it way to the surface through 

 some crevice, after the usual manner of springs, and that it is powerful 

 enough to prevent the commingling of the ocean water with it. 



The theory of the subterranean stream from the summits to sea 

 level has been further tested practically by the driving of tunnels to 

 reach the water near its source. Thus derived the water is free from 

 any possible saline contamination, and being delivered by means of a 

 ditch sloping downwards, the expense of sinking artesian wells and the 

 subsequent pumping is saved. In this way a copious daily flow has 



