Nutting.]
Natural Scale of Pure Color.
93
TABLE III.
| Color | Wave Length | |
|---|---|---|
| 1 | 420 | Violet |
| 2 | 435 | |
| 3 | 449 | |
| 4 | 463 | Blue |
| 5 | 474 | |
| 6 | 483 | |
| 7 | 490 | |
| 8 | 497 | |
| 9 | 504 | |
| 10 | 514 | |
| 11 | 527 | Green |
| 12 | 543 | |
| 13 | 556 | |
| 14 | 566 | |
| 15 | 574 | |
| 16 | 580 | Yellow |
| 17 | 588 | |
| 18 | 595 | |
| 19 | 606 | Orange |
| 20 | 626 | |
| 21 | 641 | |
| 22 | 658 | Red |
There is a widespread demand for reference standards of color in terms of which other colors may be specified. Such standards may easily be prepared of any desired hue or shade, but the great difficulties are in choosing rational and uniform divisions on the one hand and in obtaining dyes and pigments that are permanent on the other. Both difficulties would be largely obviated by the adoption of a fixed rational chromatic scale for use as a primary standard.
Washington, April 27, 1909.
2192—No. I—09——7
