APPENDIX OF TABLES

HEADS OP WATER AND CORRESPONDING PRESSURES

375

Head in Feet
Pressure Lbs. per Sq. In.
Head in Feet
Pressure Lbs. per Sq. In.
Head in Feet
Pressure Lbs. per Sq. In.
Head in Feet
Pressure Lbs. per Sq. In.

i
04335
2.3067
I
50
21.6753
80.7369
35

«*
0.6502
4-6135
2
75
32.5130
92.2707
40

2
0.8670
6.9203
3
100
43-3507
103.8046
45

4
1.0837
9.2271
4
125
54.1884
115.3384
50

3
1.3005
11.5388
5
150
65.0260
138.4060
60

4
1-7340
13.8406
6
175
75.8637
161.4736
70

5
2.1675
16.1474
7
200
86.7014
184.5415
80

10
4-3351
18.4541
8
250
108.3767
207.6090
90

15
6.5026
23.0676
10
300
130.0520
230.6768
100

20
8.6701
34.6015
15'
350
151.7273
288.3460
125

25
10.8377
46.1354
20
400
1734028
346.0152
150

30
13.0052
57-6692
25
500
216.7534
403.6844
175

40
17.3403
69.2030
30
600
260.1041
461.3536
200

DEGREES OF HARDNESS OF WATER

Clark
German
Parts per
100,000
Metric (Parts per 1,000,000}

Clark ................
I.O
1.25
0.7
0.07

German ...
0.8
1.0
0.56
0.056

Parts per 100,000 . ...
1,43
1.78
I.O
O.I

Metric (mg. per litre or parts per million) ......
14-2
17-8
10.0
1.0

pH VALUES

Pure distilled water, before exposure to atmosphere, at 22° C. = pH 7.0.
Pure distilled water after exposure to atmosphere = water + carbon dioxide

pH values over 7.0 denote alkalinity.
pH values under 7.0 denote acidity.
Hydrochloric acid = pH i.oo
Acetic acid = „ 2.86

Pure water = „ 7.00

Sodium bicarbonate = „ 8.4
Ammonium hydrate — „ 11.3
Sodium carbonate = „ n.6
Caustic soda ' = „ 13.1

< pH 5-7.