OR COLOUR BLINDNESS. 175 
tionable from indications carelessly given; they were all made 
in calm weather and in sunlight, both before and after noon. [ 
have given in Table I. a detail of one of them, performed on 
March 2, 1840, between 3 and 4 o’clock, with a grayish-blue sky. 
The glasses are there classed in the order of decrease of their 
tints to my eye ; they comprise the seven primitive colours more 
or less pure, with some of their combinations, but do not pre- 
sent that fusion by insensible degrees which is remarked in those 
of the solar spectrum. 
TABLE I. 
Experiments with Plates of Coloured Glass. 
Sa\s 
52/54 
Beles Colours according to m 
z 5 man vision. = : Colours according to the vision of a Daltonian. 
£2/5 6 
go | ae 
Aai\|A 
1 | 27 | Very dark red. Very obscure black red, indiscernible. 
2 | 1 | Less deep red. Very deep red brown, indiscernible. 
3 | 2 | Less deep red. Red. 
4 | 37 | Less deep red. Light red, of combustion. 
5 | 26 | Less deep red. Lighter red, or dark yellow. 
6 | 20 | Deep orange. Lighter red, bright, indistinct. 
7 | 35 | Less deep orange. Very bright yellow, indistinct ; red? 
8 | 34 | Less deep orange. Flame-coloured yellow, indistinct ; golden red. 
9 | 16 | Less deep orange. Fine red, light. 
10 | 15 | Deep yellow. Light red ; yellow? [the 2nd plate. 
11 | 3 | Less deep yellow. Lighter red, and more brilliant than that o: 
12| 4 | Less deep yellow. Yellowish red, indistinct. 
13 | 5 | Less deep yellow. Red of combustion. 
14 | 21 | Less deep yellow. Light green. 
“A 17 | Less deep yellow. Very light green. 
6 | 6 | Deep green. Bluish green aN 
17 | 7 | Less deep green. Bluish S ont equal colours and not distinct. 
18 | 22 | Less deep green. Fine green. 
19 | 30 | Bluish green. Light green. [the 6th and 7th plates. 
20 | 8 | Green, lighter than No.22.| Green less deep and less reddish than that o 
21 | 11 | Deep blue. Greenish blue. 
22 | 10 | Less deep blue. Blue. 
23 | 36 | Less deep blue. Light blue. 
24 | 13 | Less deep blue. Lighter blue. 
25 | 14 | Less deep blue. Lighter blue than that of plate 13. 
26 | 28 | Blue, ill-defined. Weak blue. 
27 | 12 | Dirty blue, less distinct. | Fine blue, lighter than that of plate 11. 
28 | 32 | Deep indigo. Deeper blue than that of plate 28. 
29 | 9 | Less deep indigo. Deep blue. 
30 | 33 | Less deep indigo. Fine blue, lighter. 
31 | 23 | Deep violet. Fine deep blue. 
32 | 29 | Less deep violet. Deep blue. 
33 | 24 | Less deep violet. Deep blue. 
34 | 31 | Less deep violet. Deep blue. 
35 | 25 | Less deep violet. Fine blue, weaker. 
36 | 18 | Less deep violet. Light blue, like that of plate 13. 
37 | 19 | Less deep violet. Fine sky-blue 
