HAWAII. 241 



charged any fluid lava, but seem to owe their shape to the successive 

 discharges of the loose materials. They are frequently in a lineal 

 direction, as will be observed by inspecting the map of Hawaii ; but 

 this will give little idea of their number. If reports be true relative 

 to Hualalai, hundreds may be seen from its summit, like excrescences 

 on its sides. 



One of the most striking features of this island is the difference in 

 the formation of the two great mountains, whose height so nearly 

 corresponds. The form of Mauna Loa is unique, and has been 

 increasing, from the overflow of its terminal or pit-crater, and may 

 perhaps be entirely formed by the boiling over of this, for upon 

 reflection this would not seem impossible, but, indeed, quite pro- 

 bable; and one is irresistibly drawn to this conclusion on ascend- 

 ing it. 



The extent of the lava stream flowing over the surface is very 

 great, and has been supplied by most copious springs; the recent 

 flow, for instance, covered an area of twenty square miles with a 

 thickness of twelve feet on an averasje. The height of Mauna Kea 

 has been increasing from the effects of the cone-craters, of which 

 there are now nine on the surface of its flat top : thus while one gives 

 out a molten mass, the other sends forth scoria. 



The pit-craters are also represented on the map. They have not 

 been the seat of volcanic action, yet from their extraordinary forma- 

 tion, they are deserving of that name : many exhibit a flow of lava 

 into them. The mode of their formation seems very simple, and is 

 just the eff'ect that one would suppose to arise from a sudden under- 

 mining ; but that they should always form nearly a true circle, with 

 perpendicular walls, is remarkable, and cannot be easily accounted for. 



As will have been seen, there have been copious eruptions from 

 the sides as well as from the terminal crater of Mauna Loa, and 

 among these may be reckoned that of Kilauea on its flank. It was 

 proved satisfactorily to my mind that the craters have no connexion 

 whatever with each other. An instance has been stated, where none 

 apparently existed between Judd's and the large lake in the crater of 

 Kilauea, although they were only two thousand feet apart, and it is 

 equally evident that Kilauea has none with the top of the mountain. 

 The eruption of 1832, from the terminal crater, and the one that has 

 taken place since our visit, is sufficient proof of this. All these flows 

 tend constantly to swell and increase the bulk of this mountain. 



It has been remarked already, that a grand deception in relation 



VOL. IV. 61 



