| Scale No. | Wave- length. | Reading. | Colours named by N. W. | Spectrum colours to normal vision. |
| 60 | 6728 | 3 | Both grey | Red. |
| 58 | 6520 | 10 | „ | |
| 56 | 6330 | 30 | „ | |
| 54 | 6152 | 52 | Colour “brownish,” white “grey” | |
| 52 | 5996 | 70 | „ „ „ | |
| 50 | 5850 | 81 | „ „ „ | Orange. |
| 48 | 5720 | 87 | Colour “brownish-green.” white “grey” | |
| 46 | 5596 | 90 | Colour “green,” white “grey” | |
| 44 | 5481 | 88 | „ „ | |
| 42 | 5373 | 82 | „ „ | |
| 40 | 5270 | 62·5 | „ „ | Green. |
| 38 | 5172 | 46 | „ „ | |
| 35 | 5042 | 23 | „ „ | |
| 32 | 4924 | 12·5 | „ „ | |
| 31 | 4886 | 10 | Colour “brownish-grey,” white “brownish-green.” | |
| 30·5 | 4862 | 8·5 | „ „ „ | Blue. |
| 25 | 4675 | 5 | „ „ „ | |
| 20 | 4518 | 3 | „ „ „ | |
| 15 | 4376 | 2·5 | „ „ „ | |
| 10 | 4248 | 1·5 | „ „ „ | Violet. |
| 0 | 4010 | 0·2 | „ „ „ |
Her curve of luminosity in the spectrum was next taken, and her readings are given in the table above. The curve is shown in [Fig. 40]. The shaded band beneath it applies to her curve. Miss W.’s luminosity curve is also repeated in the same figure for the sake of comparison.
An endeavour was made to form a series of colour equations with her eyesight by placing three slits in different parts of the spectrum, but without success, although a match with white was made in two positions. One slit was in the orange-red (52 of the scale), another at E, and the third at G; mixtures were made which she said matched the white, but they were so erratic that it was useless to measure the apertures. When the slit in the violet was covered up, a white patch being alongside as a comparison, she called the mixture of red and green “brownish-green”; when the slit in the red was covered she called the mixed light of green and violet “green”; and when the green slit was covered up she called the purple colour a “different kind of brown.”
When the first slit was moved into the red near the lithium line she called the colours “green,” whenever the green slit was uncovered. A piece of red glass was placed in the white reflected beam, forming a red patch, and a patch of the blue at scale No. 30·5 (λ 4862) was placed alongside, and she matched them in luminosity and in colour. (The dominant colour of the signal glass in question was λ 6220.) She finally was tested with colour discs.
To make white she required
130 G + 113 R + 117 U = 72 W + 218 B.
She was then tried with the blue and green discs alone and made a match—
258 U + 102 G = 65 W + 295 B.
An attempt was made to match with the green and red discs alone, but this failed.
She matched the red disc alone with black and white, and also the blue disc alone—