4 BULLETIN 144, U. S. DEPARTMENT OF AGRICULTURE. 
Table I. — Composition of phosphatic materials used in the manufacture of acid phosphate. 
Phosphatic 
material. 
Location. 
2£ 
5 
'o 
m 
y 
3 ^ 
2So 
.2® • 
O 

ed O 
o3 -r - 
O 

« R 
03 -^^ 
O 

u 
• 
ft 9, 
2 S w 
rd 03 
■2"Sg 
e3 SEC, 
pi On 
.2-d 0? 
u GO 
Eh 
P.ct. 
4.06 
4.14 
1.12 
P.ct. 
3.01 
3.60 
2.00 
3.67 
8.92 
3.62 
P.ct. 
P.ct. 
P.ct. 
5.28 
5.24 
8.00 
4.13 
8.05 
.29 
P.ct. 
35.38 
21.68 
31.99 
38.60 
34.42 
39.44 
7.57 
P.ct. 
76 65 
46 50 
bone. 
"Rnnp. or animal 
0.37 
.70 
1.03 
1.37 
1.59 
5.88 
1.14 
1.39 
4.07 
2.39 
1.00 
3.10 
3.04 
2.62 
73.10 
charcoal. 
Apatite: 
High grade 
Canada 
88.20 
do 
78 65 
Apatite (high 
grade). 
Bat guano 
86.10 
Porto Pico 
West Indies 
8.35 
.45 
.40 
16.52 
Guano in crusts . . 
24.36 
39.70 
35.59 
29.10 
27.20 
34.00 
23.63 
32.82 
25 to 28 
36.39 
30 to 34 
30 to 38 
27 to 32 
32 to 38 
23 to 28 
30 to 35 
27 to 36. 5 
38.73 
53.18 
Phospho-guano . . 
Phosphorite: 
High grade 
86.66 
Somme, France. 
.79 
8.55 
16.14 
9.00 
Not det. 
Not det. 
4 to 12 
4.13 
5 to 10 
2. 5 to 10 
2. 5 to 70 
2 to 7. 5 
15 to 40 
2 to 5 
1. 8 to 10 
Not det. 
9.17 
6.95 
7.07 
2.30 
10.00 
12.23 
11 to 25 
3.63 
2 to 5 
OtolO 
0to2 
77.69 
Lower grade. . . 
Do 
do... 
63 53 
5.00 
62.15 
Coprolites 
Cambridge, 
Eng. 
Suffolk, Eng 
77.70 
Do 
9.00 
5.00 
lto4 
3.00 
lto4 
3 to 8 
2. 5 to 7 
1.5 to 3. 5 
2.5to9.5 
2. 5 to 5 
. 07 to 1. 6 
.42 
6.00 
6.98 
2 to 8 
4.40 
0to3 
0to5 
0to3 
54.00 
Phosphate nod- 
Russia 
75.00 
ules. 
Do 
57 to 64 
Hard rock phos- 
phate. 
Land pebble 
phosphate. 
Brown rock phos- 
83.14 
do 
69 to 78 
Tpnnpswfl, , , , 
69 to 87 
phate. 
Blue rock phos- 
phate. 
White rock phos- 
do 
do 
Arkansas 
62 to 73 
73 to 87 
phate. 
Black rock phos- 
53 to 64 
phate. 
Brown rock phos- 
Kentucky 
69 to 80 
phate. 
. 8 to 1. 35 
1.0 
3.8 to 13.6 
4.91 
62 to 83 
phosphate. 
White phosphate 
Ocean Islands. . . 
84.65 
1 Known to the trade as bone phosphate of lime, b p. 1. 
The sulphuric acid used in the manufacture of acid phosphate is 
the ordinary " chamber acid." It ranges in specific gravity from 
1.5 to 1.6 at 60° F. and contains from 60 to 70 per cent of sulphuric 
acid. The fertilizer trade, however, is accustomed to expressing 
the strength of " chamber acid" in Baume degrees (°B). The 
manufacturer should have conversion tables at hand showing the 
specific gravity and percentage of acid corresponding to each degree 
registered by the Baume hydrometer. Part of such a table approved 
and adopted by the Manufacturing Chemists Association of the 
United States is given in Table II. 
