82 



J. D. Dana — History of the Changes in Kilauea. 



As the emptied state of the crater is the starting point for 

 this second period of the history, and future changes have a 

 degree of dependence upon it beyond what is generally under- 

 stood, Wilkes's map is presented here in outline. It is reduced 

 one-third lineally, and is so labelled as to bear its own explana- 

 tions. The ox\\y additions are B, for Lord Byron's encamp- 

 ment, and K, for Kamohoalii, the highest point on the western 

 wall. The scale of the reduced map is 5000 feet to the inch. 

 The base of the upper and lower walls is indicated on it by a 

 fine line. The position of this line in the lower pit shows a 



KILAUEA 

 U. S. EXPL. EXPED. 

 1841 > 



Encampment above the sea 3970 ft. 

 Depth to Black Ledge 650 



to bottom 



wide divergence from Mr. Drayton's sketch (PI. XII). My 

 observations put the truth between the two; the walls were 

 largely vertical, but had for long distances a high talus of lava 

 blocks, to which additions were being made by frequent falls 

 even eight months after the eruption. Only at one place was 

 the descent from the black ledge to the bottom gradual, and 

 this was on the northwestern side, where was a convenient 

 way down.* 



* See my Exped. G-eol. Rep., p. 176. Captain "Wilkes's map differs from Mr. 

 Drayton's sketch also in the small width at the neck between the lower pit and 

 Halema'uma'u. My impressions accord with the sketch, but are of no weight 



