Correspondence . 131 
nation of shales, red and black, and magnesian limestone. At this depth 
however, a change begins and at 552 feet a distinctly crystalline rock is 
encountered. Much of it is flesh red but this color is not uniform. It is 
quite hard, being about six in the scale of hardness. The chief ingredi- 
ent is feldspar with moreover macroscopic and microscopic particles of 
hornblende or p^'roxene and hematite. The nature of the supericum- 
bent rocks, together with the slight depth at which this rock was found 
make it qvnte an interesting subject for further study. 
F. W. Russell. 
Lincoln^ Neh. 
The salt ivell at Lincoln, N'cb. The 19th session of the Nebraska Legis- 
lature, in 1S85, passed a law providing for the sinking of an experimental 
well near Lincoln. Owing to divers causes the work was not begun 
until March, 1886. The main object in view was to obtain either rock 
salt or strong brine, the boring being made on one of the salt marshes of 
the state. For 205 feet the material was an alternation of sand and 
gravel. One or two flows of brine were encountered, but of low 
strength. At 205 feet the best brine was found, testing 35 degrees 
strength, and inexhaustible. Rock was found immediately imder this. 
From this poinl downward until about iioo feet there were slates, shales 
limestones and sandstones, each stratum of no very great thickness. Red 
shales and sandstones were quite abundant. Some of the limestone was 
■quite cherty. At 600 feet a fine flow of artesian water was reached 
which rose over 45 feet above the surface when piped. It was brine 
of low quality. At 82S feet another flow was encountered, which was 
a little stronger in quality and made a visible increase in quantity. 
Nothing now was found until the depth of 942 feet was reached when 
four inches of coal were passed through. At the time of the sinking 
strong hopes were entertained of finding a profitable seam after this one 
was found, but they were not realized. At 1100 feet, or thereabouts, the 
first magnesian limestone was met, and it was the chief rock onward to 
nearly 2000 feet. Here was found a sandstone very fine in grain and 
even in texture. Passing onward one finds magnesian limestone and 
red sandstone ; this last very hard in some places. The work was stop- 
ped in this same red sandstone, at the depth of 2463 feet. The boring 
ceased only on account of a technicality in the law, which made the 
funds for the purpose unavailable after a certain time. The drill hole 
was left in excellent condition, however, and there is every reason to 
"believe that the coming Legislature will make arrangements for the con- 
tinuance of the work 500 or 1000 feet further. • 
F. W. Russell. 
1 We are assured that the final report of Mr. B. P. Russell, upon this well, 
will soon appear. Mr. Russell was appointed by the board of Public 
Lands and Buildings, to superintend the boring, and his report will be 
