Table I.—Luminosity Curves for the Normal Eye (see [Fig. 20]).
| I. | II. | III. | IV. | V. |
| Scale number. | Wave- length. | Outside yellow spot. | Yellow spot. | Fovea centralis. |
| 64 | 7217 | |||
| 63 | 7082 | .. | 1 | |
| 62 | 6957 | 1 | 2 | 2 |
| 61 | 6839 | 2 | 4 | 4 |
| 60 | 6728 | 3·5 | 7 | 8 |
| 59 | 6621 | 7·5 | 12·5 | 15·5 |
| 58 | 6520 | 12·5 | 21 | 24 |
| 57 | 6423 | 19 | 33 | 37·5 |
| 56 | 6330 | 27·5 | 50 | 60 |
| 55 | 6242 | 35 | 65 | 77 |
| 54 | 6152 | 43 | 80 | 90 |
| 53 | 6074 | 52·5 | 90 | 97 |
| 52 | 5996 | 61·0 | 96 | 100 |
| 51 | 5919 | 71·0 | 99 | 100 |
| 50 | 5850 | 79·0 | 100 | 98 |
| 49 | 5783 | 84 | 99 | 95 |
| 48 | 5720 | 85 | 97 | 90 |
| 47 | 5658 | 83·5 | 92·5 | 85 |
| 46 | 5596 | 81·0 | 87 | 79 |
| 45 | 5538 | 77·0 | 81 | 72·5 |
| 44 | 5481 | 72.5 | 75 | 66 |
| 43 | 5427 | 68·0 | 69 | 59 |
| 42 | 5373 | 62·5 | 62·5 | 51 |
| 41 | 5321 | 57 | 57 | 45 |
| 40 | 5270 | 52 | 50 | 40 |
| 39 | 5221 | 46 | 42·5 | 32 |
| 38 | 5172 | 41·5 | 36 | 27·5 |
| 37 | 5128 | 37·5 | 29·5 | 22·0 |
| 36 | 5085 | 33·5 | 24 | 18 |
| 35 | 5043 | 30·0 | 18·2 | 14 |
| 34 | 5002 | 26·5 | 14·2 | 10 |
| 33 | 4963 | 24 | 10·5 | 8·4 |
| 32 | 4924 | 21 | 8·5 | 6·5 |
| 31 | 4885 | 18·5 | 7·0 | 5·5 |
| 30 | 4848 | 16·5 | 5·5 | 4·0 |
| 29 | 4812 | 14·5 | 4·7 | 3·5 |
| 28 | 4776 | 13·0 | 4·0 | 3·0 |
| 27 | 4742 | 11·5 | 3·5 | 2·0 |
| 26 | 4707 | 10·5 | 2·8 | 2·4 |
| 25 | 4675 | 9·4 | 2·3 | 2·1 |
| 24 | 4639 | 8·2 | 1·82 | 1·9 |
| 23 | 4608 | 7·3 | 1·6 | 1·5 |
| 22 | 4578 | 6·3 | 1·4 | |
| 21 | 4548 | 5·7 | 1·2 | |
| 20 | 4517 | 5·0 | 1·08 | 1·0 |
| 19 | 4488 | 4·5 | ·94 | |
| 18 | 4459 | 4·0 | ·86 | |
| 17 | 4437 | 3·6 | ·78 | |
| 16 | 4404 | 3·1 | ·70 | |
| 15 | 4377 | 2·7 | ·62 | ·62 |
| 14 | 4349 | 2·3 | ·56 | |
| 13 | 4323 | 2·1 | ·50 | |
| 12 | 4296 | 1·9 | ·45 | |
| 11 | 4271 | 1·65 | ·40 | |
| 10 | 4245 | 1·4 | ·34 | |
| 9 | 4221 | 1·2 | ·30 | |
| 8 | 4197 | 1·0 | ·26 | |
| 7 | 4174 | ·88 | ·22 | |
| 6 | 4151 | ·75 | ·18 | |
| 5 | 4131 | ·63 | ·16 | |
| 4 | 4106 | ·50 | ·14 |
Tables II. and III.—Curves of Luminosity of a Partially Red-Blind and of a Partially Green-Blind Person (see [Fig. 23]).
| Scale number. | Wave- length. | Luminosity. | |
| Red-blind. | Green-blind. | ||
| 64 | 7217 | 0 | 1 |
| 62 | 6957 | 1 | 2 |
| 60 | 6728 | 2 | 7 |
| 58 | 6520 | 6 | 21 |
| 56 | 6330 | 12 | 50 |
| 54 | 6152 | 26 | 80 |
| 52 | 5996 | 49 | 96 |
| 50 | 5850 | 70 | 98 |
| 48 | 5720 | 77 | 93 |
| 46 | 5596 | 77 | 83 |
| 44 | 5481 | 70 | 70 |
| 42 | 5373 | 61 | 55 |
| 40 | 5270 | 47 | 40 |
| 38 | 5172 | 34 | 27 |
| 36 | 5085 | 23 | 18 |
| 34 | 5002 | 14 | 10 |
| 32 | 4924 | 8·5 | 5·5 |
| 30 | 4848 | 5·5 | 3·0 |
| 28 | 4776 | 4·0 | 2·5 |
| 26 | 4707 | 2·7 | 2·0 |
| 24 | 4639 | 1·8 | 1·8 |
| 22 | 4578 | 1·35 | 1·4 |
| 20 | 4517 | 1·1 | 1·1 |
Table IV.—Luminosity of Spectrum Reduced in Intensity, so that D = 1/132·5 Amyl Lamp 1 Foot Distant (see [Fig. 25]).
| Scale number. | Mean reading. | Mean reading, reduced to 100 max. | P. and Q.’s readings, 100 max. | Persistency curve for the centre of the eye. |
| 55·6 | ·5 | ·6 | 2 | 2 |
| 53·6 | 5·5 | 7·0 | 3·6 | 3·6 |
| 51·6 | 13 | 16·7 | 8 | 8 |
| 49·6 | 23 | 29·7 | 22 | 22 |
| 47·6 | 40 | 50·0 | 44 | 44 |
| 45·6 | 57 | 71·2 | 69 | 69 |
| 43·6 | 70 | 87·5 | 93 | 93 |
| 41·6 | 79 | 98·7 | 100 | 99·5 |
| 39·6 | 78 | 97·5 | 99·5 | 98·5 |
| 37·6 | 74 | 92·5 | 96 | 93 |
| 35·6 | 66 | 82·5 | 89 | 84 |
| 33·6 | 55 | 68·7 | 77·5 | 71 |
| 31·6 | 44·5 | 55·2 | 61 | 53·5 |
| 29·6 | 35 | 43·7 | 45·5 | 36·5 |
| 27·6 | 24 | 30·0 | 33·5 | 24 |
| 25·6 | 17 | 21·7 | 25 | 16 |
| 23·6 | 13 | 16·7 | 18 | 10 |
| 21·6 | 10 | 12·5 | 13 | 8 |
| 19·6 | 8 | 10·0 | 9·5 | 6 |
| 13·6 | 3 | 3·7 | 4·2 | 3 |
| 9·6 | 2 | 2·5 | 2·5 | 2 |
Table V.—Limit of Colour Vision (see [Fig. 26].).
| Scale Number. | Wave- Length. | Mean reading of the colour limit of the spectrum D, being 1 amyl lamp in 1/10000ths. | Luminosity of the ordinary spectrum. | Luminosity of the rays when each colour disappears, each ray having the original luminosity of 1 amyl lamp in 1/100000ths. |
| 61 | 6839 | 120 | 4 | 48·0 |
| 60 | 6728 | 67 | 7 | 46·9 |
| 58 | 6520 | 26 | 21 | 54·6 |
| 56 | 6330 | 13 | 50 | 65·0 |
| 54 | 6152 | 9·5 | 80 | 76·0 |
| 52 | 5996 | 9·0 | 96 | 86·4 |
| 50 | 5850 | 9·0 | 100 | 90·0 |
| 48 | 5720 | 9·0 | 97 | 87·3 |
| 44 | 5481 | 9·5 | 75 | 71·3 |
| 40 | 5270 | 10·5 | 50 | 52·5 |
| 36 | 5085 | 12·5 | 24 | 30·0 |
| 32 | 4924 | 18 | 8·5 | 15·3 |
| 28 | 4776 | 32 | 4·0 | 12·8 |
| 24 | 4639 | 55 | 1·8 | 12·0 |
| 20 | 4517 | 90 | 1·08 | 9·7 |
| 16 | 4404 | 160 | ·70 | 11·2 |
| 12 | 4296 | 250 | ·45 | 11·0 |
| 8 | 4197 | 400 | ·26 | 10·4 |
| 4 | 4106 | 700 | ·14 | 9·8 |
Table VI.—Extinction by Central Portion of Normal Eye (see [Fig. 28]).
| I. | II. | III. | IV. | V. | VI. |
| Scale number. | Wave- length. | E. Reduction of original luminosity in millionths to cause extinction. | L. Luminosity of original beam. | (E × L) / 100 | Persistency curve 650 / E (Maximum = 100). |
| 64 | 7217 | 55,000 | |||
| 63 | 7082 | 30,000 | 1 | 300·0 | |
| 62 | 7957 | 15,000 | 2 | 300·0 | |
| 61 | 6839 | 7500 | 4 | 300·0 | |
| 60 | 6728 | 3750 | 7 | 262·5 | |
| 59 | 6621 | 1900 | 12·5 | 237·5 | ·34 |
| 58 | 6520 | 1050 | 21 | 220·5 | ·62 |
| 57 | 6423 | 650 | 33 | 214·5 | 1·0 |
| 56 | 6333 | 380 | 50 | 190·0 | 1·71 |
| 55 | 6242 | 272 | 65 | 176·8 | 2·38 |
| 54 | 6152 | 196 | 80 | 156·0 | 3·32 |
| 53 | 6074 | 140 | 90 | 126·0 | 4·64 |
| 52 | 5996 | 97 | 96 | 93·12 | 6·70 |
| 51 | 5919 | 57 | 99 | 56·43 | 11·40 |
| 50 | 5850 | 35 | 100 | 35·0 | 18·6 |
| 49 | 5783 | 24 | 99 | 23·76 | 27·1 |
| 48 | 5720 | 17 | 97 | 16·49 | 38·2 |
| 47 | 5658 | 12·6 | 92·5 | 11·65 | 51·6 |
| 46 | 5596 | 10·2 | 87 | 8·87 | 63·7 |
| 45 | 5538 | 8·6 | 81 | 6·97 | 75·6 |
| 44 | 5481 | 7·4 | 75 | 5·55 | 87·8 |
| 43 | 5427 | 6·7 | 69 | 4·62 | 97·0 |
| 42 | 5373 | 6·55 | 62·5 | 4·09 | 99·5 |
| 41 | 5321 | 6·5 | 57 | 3·705 | 100 |
| 40 | 5270 | 6·55 | 50 | 3·27 | 98·5 |
| 39 | 5221 | 6·65 | 42·5 | 2·83 | 97·5 |
| 38 | 5172 | 6·85 | 36 | 2·46 | 95·0 |
| 37 | 5128 | 7·2 | 29·5 | 2·12 | 90·0 |
| 36 | 5085 | 7·6 | 24 | 1·82 | 81·3 |
| 35 | 5043 | 8·15 | 18·2 | 1·48 | 80·0 |
| 34 | 5002 | 8·8 | 14·2 | 1·25 | 74·0 |
| 33 | 4963 | 10·2 | 10·5 | 1·07 | 63·0 |
| 32 | 4924 | 11·6 | 8·5 | ·988 | 56·0 |
| 31 | 4885 | 13·6 | 7·0 | ·952 | 47·7 |
| 30 | 4848 | 16·3 | 5·5 | ·896 | 40·0 |
| 29 | 4812 | 20·5 | 4·7 | ·963 | 31·7 |
| 28 | 4776 | 26·0 | 4·0 | 1·040 | 25·0 |
| 27 | 4742 | 31·0 | 3·5 | 1·085 | 20·9 |
| 26 | 4707 | 38·5 | 2·8 | 1·078 | 16·9 |
| 25 | 4674 | 46·0 | 2·3 | 1·058 | 14·1 |
| 24 | 4639 | 56·0 | 1·82 | 1·019 | 11·6 |
| 23 | 4608 | 67·0 | 1·6 | 1·072 | 9·7 |
| 22 | 4578 | 80 | 1·4 | 1·120 | 8·41 |
| 21 | 4548 | 95 | 1·2 | 1·140 | 7·22 |
| 20 | 4517 | 107 | 1·08 | 1·156 | 6·1 |
| 19 | 4488 | 124 | ·94 | 1·165 | 5·23 |
| 18 | 4459 | 140 | ·86 | 1·204 | 4·64 |
| 17 | 4437 | 160 | ·78 | 1·228 | 4·1 |
| 16 | 4404 | 180 | ·70 | 1·260 | 3·60 |
| 15 | 4377 | 200 | ·62 | 1·240 | 3·25 |
| 14 | 4349 | 220 | ·56 | 1·232 | 2·95 |
| 13 | 4323 | 240 | ·50 | 1·200 | 2·7 |
| 12 | 4296 | 270 | ·45 | 1·215 | 2·4 |
| 11 | 4271 | 300 | ·40 | 1·200 | 2·18 |
| 10 | 4245 | 335 | ·34 | 1·139 | 1·94 |
| 9 | 4221 | 375 | ·30 | 1·125 | 1·73 |
| 8 | 4197 | 430 | ·26 | 1·118 | 1·51 |
| 7 | 4174 | 490 | ·22 | 1·078 | 1·32 |
| 6 | 4151 | 510 | ·18 | ·918 | 1·27 |
| 5 | 4131 | 640 | ·16 | 1·024 | 1·01 |
| 4 | 4106 | 750 | ·14 | 1·050 | 0·86 |