62 
LAKAMIE BASIN, WYOMING. 
Lakes, 12 miles northwest of Rock Creek post-office. They are all in 
depressions in the Cretaceous shales or the overlying alluvial deposits, 
and are the result of the evaporation either of surface drainage or of 
local springs, or perhaps of both. 
The Downey Lakes are three in number and occupy shallow 
depressions extending in a northeast-southwest direction a short dis- 
tance west of Alkali Creek. They average a quarter of a mile long 
and 150 yards wide and have a total area of about 100 acres. The 
middle lake is somewhat larger than the others and is covered with 
a crust of nearly solid soda upon which a light corduroy bridge is 
laid. The deposit consists of alternations of clean sulphate of soda, 
mud, and mixtures of soda .and mud, extending to a depth of 6 to 11 
feet. The upper crust is nearly pure white and several inches thick. 
The northern lake is the lowest and smallest, but its salts are purer 
and there is less mud. An analysis of clean crystals from its surface 
made by E. E. Slosson gave more than 95 per cent of hydrous sodium 
sulphate. The southern lake is slightly higher than the middle one, 
but it contains water and is miry. Apparently it does not contain 
as much soda as the others. According to Slosson's analysis, made 
in October, 1901, its water is a very strong solution of sodium and 
magnesium sulphates with some sodium chloride and sodium car- 
bonate. The specific gravity is 1.261. 
The following are Slosson's analyses a of the waters and salts on 
material collected by him or W. C. Knight in 1899 and 1901: 
Analyses of the Downey 
Lakes « 
soda deposits. 
1 
(1899). 
2 
(1901). 
55.43 
2.24 
39.17 
.12 
2.24 
3 
(1899). 
74.60 
'"&.9S 
1. 16 
17.31 
4 
(1901). 
5 
(1901). 
75.89 
.02 
11.50 
.45 
12.08 
.06 
6 
(1901). 
7 
(1901). 
Hypothetical combinations: 
Water 
44.41 
.11 
28. 24 
.28 
26.96 
72. 79 
.13 
12.77 
.86 
13.40 
.05 
49. 29 
.51 
19. 67 
.50 
30.03 
55.94 
.10 
Sodium sulphate (Na 2 S0 4 ) 
Sodium chloride (NaCl) 
41.02 
.12 
1.82 
.80 
Calculated as dry salts: 
50.90 
.50 
48.60 
92.54 
.28 
5.29 
25. 61 
5.28 
70.11 
47.18 
3. 17 
49.47 
.18 
47.74 
1.86 
50.16 
.24 
39.18 
1.00 
59.82 
95.46 
.28 
Magnesium sulphate (MgS0 4 ) 
4.26 
1.89 
1. Sample of crystallized salts taken under water in middle Downey Lake. 
2. From middle lake. Consists of large, clear crystals of mirabilite mixed with mud and water. It 
was obtained by blasting through the crust to the depth of about 6 feet near the middle of the lake. 
3. Sample of the solution standing above the salts represented by No. 1. 
4. Solution which filled the blast hole when No. 2 was taken. 
5. Water from the southern lake. 
6. Sample of crystallized salts found in a small ditch leading out of the southern lake 
7. Sample of the purest crystals obtainable from the extreme north end of the northern lake. 
Knight reports tests at the Downey Lakes, where several holes 
were sunk through the deposit. In the course of a few hours these 
a Bull. Univ. Wyoming No. 49, 1901, p. 110. 
