and the MucUumps of the Mississippi. 427 



in the mud-lump gas, in accordance with the presumable more 

 advanced stage of decay existing in the former locality. 



Mudlump Spring Waters.~h\ taking specimens, common 

 quart bottles were filled by immersion in the craters them- 

 selves, and immediately sealed. The liquid mud thus obtained 

 would, after a while, separate into a lower stratum of pretty 

 solid mud, and an upper one of clear water, in varying propor- 

 ^^^^: For analysis, the latter was carefally decanted, and the 

 turbid part rapidly filtered through a Bunsen's pressure filter, 

 and measured. 400 ccm. were then boiled to precipitate car- 

 bonates and silica, the filtrate re-diluted to the original bulk, 

 and from 50 to 100 ccm. used in the determination, in separate 

 portions, of chlorine, of lime and magnesia, and of sulphuric 



lor an approximate determination of the solid residue, for the 

 sake of roughly controlling the final resulta* 



f give below, in tabular form, the results of these analyses ; 

 presented in three different forms, for the sake of ready com- 

 panson with the composition of sea-water, from which they 

 seem to be derived by a series of reactions easily understood 

 iroin the nature and condition of the materials with which they 

 are associated. 



I Water from the basin of a spring on a mudlump off Stake 

 ■^land. Southwest Pass. Evolves gas and water in about equal 

 proportions, no mud, but only fine sandy matter; and water 

 flows off clear over the rim of the basin, which is two feet above 

 tiae level, and at the foot of a large extinct cone with a lagoon, 

 surrounded by a high rim, in the center. 



vV ater about I of the bulk ii^ bottle, the rest fine sand, 

 laste, very salty : color, slightly yellowish; turns brownish 

 turbid very quickly on exposure to air. Coll. Dec. 3, 1867. 



-U. Water from a mudlump spring on Northeast Pass, col- 

 lected by H. L. Marindin, of U. S. Coast Survey schr. Yarina, 

 in February, 1867. 



According to the recollection of one of the crew, this speci- 

 men was taken from the same cone as the following one (No. 



Water clear, faintly yellowish, about i by bulk of the con- 

 sents ; the rest sandy mud. Turns turbid rapidly on exposure 



