50 Kilauca and Manna Loa. 



feet above the general floor. This was "in violent ebullition, with an apparent flow 

 from south to north, caused by the escape of elastic fluids, throwing up the spray in 

 many parts thirty to forty feet." He also mentions that this lake (Halemaumau) 

 overflowed at times."" 



It took Kilauea nine years to fill up after the eruption of 1823; and now for 

 eight years the process had been continued until the lava had reached a level nearly 

 a hundred feet above the level in 1832. The force tending to rupture the mountain 

 may be readily calculated, assuming the pressure of ever}' twelve feet of lava to be 

 fifteen pounds to the sc|uare inch ; if the crater is emptied to a depth of four hundred 

 feet, and in recent years the depth has been seven hundred feet, we have a pressure of 

 five hundred pounds to the square inch. It must be remembered that the mountain 

 wall is by no means solid and compact, and although successive discharges may 

 strengthen some volcanic mountains, here the effect seems to be quite the contrary, 

 owing to the extreme fluidity of the lava which runs off, leaving tunnels and caverns 

 instead of solid interlacing d3^kes; consequentlj^ the discharges iisuallj' follow the 

 same general direction. 



There now comes into this history a man whose name has for man}- j-ears been 

 connected with Kilauea as its faithful observer and reporter; the Rev. Titus Coan, 

 or Father Coan as those of us who knew and loved him preferred to call him. 

 This excellent missionar}- was stationed at Hilo and the volcano was included in his 



parish, and he cared for it as he did for all his parishioners. His letters 

 1840 to the Missionar}- Herald, Silliman's Journal, Professor Dana, and myself, 



contain much information of the crater he loved to visit, and will be freely 



i;sed here. Father Coan was in Oahu when the great eruption of 1840 took place, 



but on his return to Hawaii he at once began his investigations. In a letter dated 



September 25, 1840, he gives us the result: 



For several years past the great crater of Kilauea has been rapidly filling up by the rising of 

 the superincumbent crust, and by the frequent gushing forth of the molten sea below. In this man- 

 ner the great basin below the black ledge, which has been computed from three to five hundred feet 

 deep, was long since filled up by the ejection and cooling of successive masses of the fiery fluid. 

 These silent eruptions continued to occur at itUervals, until the black ledge was repeatedly over- 

 flowed, each cooling and forming a new layer from two feet thick and upwards, until the whole area 

 of the crater was filled up, at least fifty feet above the original black ledge, and thus reducing the 

 whole depth of the crater to less than nine hundred feet. This process of filling up continued till 

 the latter part of May, 1S40, when, as many natives testify, the whole area of the crater became one 

 entire sea of ignifluous matter, raging like old ocean when lashed into a fur}' by a tempest. For 

 several days the fires raged with fearful intensity', exhibiting a scene awfull}' terrific. The infuriated 

 waves sent up infernal sounds, and dashed with such maddening energy against the sides of the 

 awful cauldron, as to shake the solid earth above, and to detach huge masses of overhanging rocks, 

 which, leaving their ancient beds, plunged into the fiery gulf below. So terrific wa.*; the scene that no 



^'London Atheneum, Nov. 14, 1840, p. 909. [428] 



