Per cent. by weight of Lb. of actual NaOH contained in 1 gallon of lye made from commercial caustic of
Degrees Twaddell. Specific gravity. Na2O. NaOH. 77 per cent. 74 per cent. 70 per cent.
1 1.005 0.368 0.474 0.048 0.046 0.043
2 1.010 0.742 0.957 0.097 0.092 0.087
3 1.015 1.114 1.436 0.146 0.131 0.129
4 1.020 1.480 1.909 0.194 0.185 0.180
5 1.025 1.834 2.365 0.243 0.231 0.219
6 1.030 2.194 2.830 0.291 0.278 0.262
7 1.035 2.521 3.252 0.335 0.320 0.303
8 1.040 2.964 3.746 0.389 0.371 0.350
9 1.045 3.244 4.184 0.438 0.417 0.393
10 1.050 3.590 4.631 0.486 0.461 0.438
11 1.055 3.943 5.086 0.536 0.510 0.483
12 1.060 4.292 5.536 0.586 0.558 0.528
13 1.065 4.638 5.982 0.636 0.607 0.573
14 1.070 4.972 6.413 0.680 0.653 0.617
15 1.075 5.311 6.911 0.742 0.707 0.668
16 1.080 5.648 7.285 0.786 0.749 0.709
17 1.085 5.981 7.715 0.836 0.798 0.755
18 1.090 6.311 8.140 0.886 0.845 0.800
19 1.095 6.639 8.564 0.937 0.894 0.846
20 1.100 6.954 8.970 0.986 0.941 0.890
21 1.105 7.276 9.386 1.037 0.989 0.938
22 1.110 7.594 9.796 1.087 1.037 0.981
23 1.115 7.910 10.203 1.137 1.123 1.026
24 1.120 8.223 10.607 1.187 1.175 1.071
25 1.125 8.583 11.107 1.238 1.181 1.117
26 1.130 8.893 11.471 1.296 1.237 1.170
27 1.135 9.251 11.933 1.354 1.292 1.122
28 1.140 9.614 12.401 1.413 1.350 1.277
29 1.145 9.965 12.844 1.470 1.413 1.337
30 1.150 10.313 13.303 1.529 1.460 1.381
31 1.155 10.666 13.859 1.600 1.528 1.445
32 1.160 11.008 14.190 1.646 1.541 1.456
33 1.165 11.347 14.637 1.705 1.627 1.539
34 1.170 11.691 15.081 1.764 1.684 1.593
35 1.175 12.025 15.512 1.822 1.739 1.645
36 1.180 12.356 16.139 1.904 1.817 1.719
37 1.185 12.692 16.372 1.942 1.853 1.753
38 1.190 13.016 16.794 1.998 1.887 1.804
39 1.195 13.339 17.203 2.055 1.962 1.856
40 1.200 13.660 17.629 2.122 2.026 1.916
41 1.205 14.058 18.133 2.185 2.085 1.973
42 1.210 14.438 18.618 2.252 2.147 2.033
43 1.215 14.823 19.121 2.323 2.221 2.097
44 1.220 15.124 19.613 2.392 2.280 2.161
45 1.225 15.502 19.997 2.444 2.338 2.206
46 1.230 15.959 20.586 2.562 2.417 2.285
47 1.235 16.299 20.996 2.593 2.475 2.341
48 1.240 16.692 21.532 2.669 2.548 2.410

Per cent. by weight of Lb. of actual NaOH contained in 1 gallon of lye made from commercial caustic of
Degrees Twaddell. Specific gravity. Na2O. NaOH. 77 per cent. 74 per cent. 70 per cent.
49 1.245 17.060 22.008 2.739 2.615 2.474
50 1.250 17.424 22.476 2.809 2.681 2.536
51 1.255 17.800 22.962 2.881 2.750 2.602
52 1.260 18.166 23.433 2.952 2.818 2.666
53 1.265 18.529 23.901 3.020 2.886 2.730
54 1.270 18.897 24.376 3.095 2.955 2.795
55 1.275 19.255 24.858 3.171 3.027 2.863
56 1.280 19.609 25.295 3.237 3.090 2.932
57 1.285 19.961 25.750 3.308 3.158 2.988
58 1.290 20.318 26.210 3.381 3.227 3.053
59 1.295 20.655 26.658 3.452 3.364 3.117
60 1.300 21.156 27.110 3.524 3.394 3.182
61 1.305 21.405 27.611 3.603 3.439 3.253
62 1.310 21.785 28.105 3.682 3.514 3.224
63 1.315 22.168 28.595 3.760 3.593 3.395
64 1.320 22.556 29.161 3.849 3.674 3.475
65 1.325 22.926 29.574 3.919 3.742 3.539
66 1.330 23.310 30.058 3.997 3.816 3.610
67 1.335 23.670 30.535 4.072 3.891 3.681
68 1.340 24.046 31.018 4.156 3.967 3.754
69 1.345 24.410 31.490 4.232 4.042 3.824
70 1.350 24.765 31.948 4.312 4.116 3.894
71 1.355 25.152 32.446 4.396 4.196 3.970
72 1.360 25.526 32.930 4.478 4.274 4.043
73 1.365 25.901 33.415 4.561 4.354 4.109
74 1.370 26.285 33.905 4.645 4.434 4.194
75 1.375 26.650 34.382 4.728 4.513 4.269
76 1.380 27.021 34.855 4.810 4.592 4.344
77 1.385 27.385 35.328 4.893 4.670 4.418
78 1.390 27.745 35.795 4.975 4.794 4.493
79 1.395 28.110 36.258 5.058 4.828 4.567
80 1.400 28.465 36.720 5.141 4.907 4.642
81 1.405 28.836 37.203 5.227 4.989 4.720
82 1.410 29.203 37.674 5.312 5.071 4.797
83 1.415 29.570 38.146 5.397 5.135 4.873
84 1.420 29.930 38.610 5.482 5.233 4.950
85 1.425 30.285 39.071 5.567 5.314 5.027
86 1.430 30.645 39.530 5.653 5.396 5.104
87 1.435 30.995 39.986 5.738 5.467 5.181
88 1.440 31.349 40.435 5.823 5.558 5.258
89 1.445 31.700 40.882 5.908 5.640 5.335
90 1.450 32.043 41.335 5.923 5.721 5.412
91 1.455 32.460 41.875 6.093 5.816 5.502
92 1.460 32.870 42.400 6.191 5.909 5.608
93 1.465 33.283 42.935 6.290 6.004 5.679
94 1.470 33.695 43.467 6.389 6.009 5.769
95 1.475 34.092 43.980 6.487 6.193 5.856
96 1.480 34.500 44.505 6.586 6.287 5.948
97 1.485 34.899 45.013 6.685 6.381 6.035
98 1.490 35.245 45.530 6.784 6.476 6.126
99 1.495 35.691 46.041 6.884 6.571 6.216
100 1.500 36.081 46.545 6.982 6.665 6.303

(From Soaps, by G. H. Hurst, published by Scott, Greenwood & Son.)

APPENDIX D.

TABLE OF STRENGTH OF CAUSTIC POTASH SOLUTIONS AT 60° F.

Specific gravity. Degrees Twaddell. Per cent. KOH. Lb. of KOH per gal.
1.060 12 5.59 0.59
1.110 22 11.31 1.25
1.150 30 15.48 1.77
1.190 38 19.29 2.21
1.230 46 23.22 2.84
1.280 56 27.87 3.56
1.330 66 31.32 4.16
1.360 72 35.01 4.76
1.390 78 38.59 5.36
1.420 84 40.97 5.81
1.440 88 43.83 6.31
1.470 94 47.16 6.93
1.520 104 51.09 7.76
1.600 112 55.62 8.89
1.680 136 60.98 10.24
1.780 156 67.65 12.04
1.880 176 75.74 14.23
2.000 200 86.22 17.24

(From Soaps, by G. H. Hurst, published by Scott, Greenwood & Son.)