144 Extracts from the Journals. [Jan., 



No. II. — Specimen of the present Soil of the Valley of Korosco , 

 taken at a height of three feet above the Mile. 



This earth is also partly in lumps and partly in powder. The 

 former exhibit no marks of stratification, and so far as can be ob- 

 served, have no tendency to part in one direction more than in 

 another. The texture is open and porus, but the pores are not 

 filled as in No. 1, with any deposite of white matter, except here 

 and there a rather light gray in the intei'ior of the cavities. In 

 some of the lumps, minute rootlets are seen traversing the mass 

 in different directions. The color of this soil is considerably 

 darker than that of No. 1, due in part no doubt to the absence of 

 carbonate of lime. Ferruginous particles abound in this, as in 

 the preceding specimen, but those of mica are of far less frequent 

 occurrence. 



Time has allowed me to make but a few trials to ascertain the 

 composition of this soil, as it was believed to be of more interest 

 to determine the relative characters of the oldest and of the most 

 recent ones, rather than that of an intermediate period. By 

 twice drying in the inverted syphon apparatus, and in the last 

 instance passing over it 200 cubic inches of air, thorouo-hly dry, it 

 lost 2.6 per cent. By treatment in the apparatus for separatino- 

 carbonic acid, and boiling five times successively to expel the last 

 atom of that material, using a solution of pure baryta to ascertain 

 when the escaping air, expelled in boiling, ceased to be mixed 

 with that acid, it was found that the amount of carbonic acid was 

 only 1.7 per cent equivalent to 3.9 per cent of carbonate of lime. 

 On separating the soil with the sieve, the finest portion — that 

 passing through the gauze sieve — was found to afford decidedly 

 more magnetic oxide of iron, than specimen No. 1. 



No. III. — Specimen of the Earth newly deposited at Korosco, the 

 18tk of August. 1844. 



This specimen is entirely in powder, and of a color very nearly 

 approaching that of No. 2. 



Particles of mica are rather rare occurrence. A few minute 

 fragments of straw or grass are detected, and by a gauze sieve, of 

 which the meshes are 100 to the inch, and the spaces to the 

 threads as 2 i to 1 in diameter, making the open spaces j-/o^ of an 

 inch square only, 22 per cent of this earth was arrested. A 

 quantity of very fine fibrous or downy matter was also collected 

 by the sieve. Portions of both the coarser and the finer parts of 

 this soil are attracted by the magnet, 4-tenths of one per cent 

 being found in an average portion of it. On being washed, the 

 coarser part is found to be a sand, composed of quartz, red and 

 white, fragments of schorl, and garnets, of magnet oxide of iron, 



