J. D. Dana — History of the Changes in Kilauea. 359 



tion of 1825. It is an interesting and important fact that while 

 the fissures about the northeast end of Kilauea are concentric 

 with the outline of the crater (Kilauea' iki being included with 

 it), those at the south end are nearly all longitudinal, or in the 

 direction of the longer diameter, southwestward. Moreover, 

 as is well known, they extend on for twelve to fifteen miles to 

 the southwest. They are very numerous, more so than is 

 shown on any map or recorded in any description ; and some 

 are very deep in places, giving off hot air, steam and sulphur- 

 ous acid fumes in great volume. While some of them date 

 from 1868, and others from 1886,* still others existed back of 

 all records. 



The subsidence that has gone on over this southwestern fis- 

 sured area has not left any satisfactory evidence of its amount. 

 We know only, that (as the Government map teaches) the sur- 

 face is about 280 feet below the level of the Yolcano House 

 and 395 below that of the Uwekahuna station. 



14. Volcanic sand, stones and scoria, covering all the borders of 

 Kilauea, from an eruption about the year 1789. — The account of 

 the eruption of 1789, gathered from the natives by the Rev. I. 

 Dibble and published in his "History of the Sandwich Islands"f 

 (1843), mentions that for two nights there were eruptions with 

 ejections of "stones and cinders;" soon followed the rising of 

 a dense, dark cloud from the crater, with thundering and light- 

 ning, and then "an immense volume of sand and cinders which 

 were thrown to a great height, and came down in a destructive 

 shower for many miles around." 



The "sand and cinders" of this eruption (the latter usually 

 called on the island pumice,% on account of its extreme light- 

 ness, and first mentioned by Ellis, who says " light as a sponge") 

 are well known to cover an area of " many miles" to the south- 

 west of the crater; but the accounts of the region have said 

 nothing about the stones until the publication of Professor C. 

 H. Hitchcock in Science of February last, after his visit to the 

 crater in the summer of 1886. He there reports that : 



" Standing at Keanakakoi, one sees to the southwest and 

 south a stretch of volcanic sand and debris fully equal in dimen- 

 sions to Kilauea itself. On examining more closely the material 

 called 'gravel' on the map, 'it was seen to consist of material 



* Mr. Emerson distinguishes the two sets in his paper in the last volume of this 

 Journal. An exact mapping and numbering of all the fissures, as well as deter- 

 mination of levels, about the Kilauea border would be a very important step 

 toward a correct reading of the future history. 



f The facts which Mr. Dibble publishes are cited in my Expl. Exped. Report, 

 on page 183. 



\ Pumice is the scoria of a trachytic or some orthoclase-bearing lava, with the 

 vesicles linear. 



