little material difference in the composition of the lava and ash, the 
source of Hawaiian soils narrows down to volcanic basalts of a more 
or less uniform composition. Analyses of lava, volcanic ash, and 
coral sand are given in the following table : 
Analyses of lava, volcanic ash, and coral sand. 
Constituents. 
Lava. 
From Oahu. 
Sample 
B. 
Sample 
E. 
Sample 
F. 
From Hawaii. 
Sample 
No. 501. 
Sample 
No. 502. 
Sample 
No. 503. 
Silica (Si0 2 ) 
Alumina (AI2O3) 
Ferric oxid (Fe 2 3 ) 
Ferrous oxid (FeO) 
Manganese oxid (M^O^ 
Lime(CaO) 
Magnesia (MgO) 
Potash(K 2 0) 
Soda(Na 2 0) 
Sulphur trioxid (S0 3 ) 
Phosphorus pentoxid (P2O5) 
Titanic oxid (Ti 2 ) 
Moisture 
Per cent. 
52.45 
11.49 
3.66 
6.90 
.36 
10.32 
5.81 
.89 
2.44 
.20 
.38 
4.07 
1.02 
Per cent. 
52.15 
12.57 
3.36 
7.07 
.50 
8.54 
6.51 
.84 
2.64 
.61 
.28 
4.07 
.94 
Per cent. 
51. 98 
15.85 
2.90 
6.84 
.92 
9.57 
5.61 
.97 
2.70 
.51 
.22 
1.50 
1.04 
Per cent. 
52.24 
16.00 
3.73 
5.89 
.68 
9.54 
5.90 
.86 
2.65 
.53 
.11 
1.50 
.54 
Per cent. 
48.88 
12.84 
.30 
8.52 
.31 
9.55 
10.29 
.75 
1.44 
.33 
.21 
2.54 
4.45 
Per cent. 
48.55 
14.83 
2.44 
6.07 
.66 
8.56 
14.22 
.72 
1.56 
.19 
.22 
2.15 
.09 
Per cent. 
52.07 
14.12 
2.64 
-7.01 
.72 
10.71 
7.51 
.74 
1.93 
.35 
.24 
2.42 

Constituents. 
Lava. 
From II awaii. 
Sample 
Sample 
No. 504. 
No. 505. 
Per cent. 
Per cent. 
51.25 
49.94 
14.36 
14.42 
3.30 
1.04 
6.43 
8.01 
.44 
.20 
10.65 
11.59 
9.12 
9.08 
.64 
.80 
1.96 
1.79 
.33 
.33 
.17 
.26 
2.35 
2.86 


Sample 
No. 519. 
Volcanic ash. 
From Maui. 
Sample 
No. 506. 
Sample 
No. 507. 
From 
Oahu. 
Sample 
No. 132. 
Coral 
sand. 
From 
Oahu. 
Sample 
No. 227. 
Silica (Si0 2 ) 
Alumina (A1 2 3 ) 
Ferric oxid (Fe 2 3 ) 
Ferrous oxid (FeO) 
Manganese oxid (Mn 2 04) — 
Lime(CaO) 
Magnesia (MgO) 
Potash(K 2 0) , 
Soda (Na 2 0; 
Sulphur trioxid (S0 3 ) 
Phosphorus pentoxid (P 2 5 ) 
Titanic oxid (Ti0 2 ) 
Moisture 
Per cent. 
50.69 
15.62 
.49 
4.65 
.28 
11.14 
6.55 
.90 
2.56 
.78 
.34 
5.53 
.10 
Per cent. 
45.54 
17.42 
8.60 
Per cent. 
46.98 
16.62 
7.08 
1.17 
8.90 
6.14 
1.82 
2.92 
.36 
.63 
6.00 
.74 
.18 
7.16 
5.58 
1.32 
2.62 
.46 
.59 
6.60 
1.55 
Per cent. 
36.82 
18.08 
10.40 
4.32 
.46 
9.52 
.54 
5.62 
10.20 
.18 
.70 
5.50 
.09 
Per 
cent. 
2.60 

.21 

92.40 
2.90 
.31 
.46 
.55 
.21 
j0 
Samples A, B, E, and F are from unaltered lava in the Wahiawa 
district of Oahu. Nos. 501 to 505, inclusive, are from the different 
flows of Mauna Loa on the Island of Hawaii. No. 501 was taken 
from the flow of 1823 and had undergone a slight decomposition; 
No. 502 was taken from the flow of 1868 and showed slight changes 
in appearance, due probably to hydration and leaching; No. 503 
came from the flow of 1883; No. 504 from that of 1907; and No. 
505 from the small overflow of 1910 at Kilauea. No. 519 is a sample 
