COLORING MATTERS. 



29 



49. Bielirich Scarlet Continued. 



0.585/1. Transparent to orange and 

 red. Same empirical formula as No. 

 48 and almost identical visible ab- 

 sorption. 



50. Wool Black. (A.) Sodium salt of sul- 



pbobenzene-azo - sulphobenzene-azo- 

 /'-tolyl-^-naphthylaniiiie. 



Figf. 67, pi. 17; No. 166, S. & J. 



niuish-black powder. In solution pur- 

 ple, light purple. 



5.56 g. per liter (filtered). 



Angle 35.1'. Depth o to 0.32 mm. 



Hazy band in yellow spreading indefi- 

 nitely into the orange. Transmits 

 bright red. At 0.49/1 a region of ab- 

 sorption commences which seems to 

 consist of a hazy central band with 

 a weak, washed-out companion on 

 each side. The chief maximum is 

 about o.54/t. Absorption is very weak 

 from o.6o/i to 0.63/1. A very concen- 

 trated solution shows that the max- 

 imum of transparency is near 0.44/1. 



51. Ponceau 6 R B. (A.) Sodium salt of 



sulphotoluene - azo - toluene - azo - /3- 

 naphthol-a-sulphonic acid. 



Fig. 56, pi. 14; No. 169, S. & J. 



Reddish-brown powder. In solution 

 , scarlet red, pink. 



5.38 g. per liter. 



Angle 31.2'. Depth o to 0.29 mm. 



Strong band in the green which is 

 more definite on the blue side than 

 on the yellow border. Strong band 

 from 0.465/1 to 0.565/1. The maxi- 

 mum is at 0.5 i/i. The band is prob- 

 ably composed of two unresolved 

 bands of which the weaker lies nearer 

 the red. Transparent from 0.565/1 to 

 0.63/1. 



52. Blue-Black. (B.) Sodium salt of sulpho- 



/8-naphthalene - azo - a - naphthalene- 

 azo-/8-naphthol-disulphonic acid. 



No. 186. S. & J.* 



Bluish-black powder. In solution bluish 

 violet, violet. 



6.69 g. per liter (filtered). 



Angle 33.2'. Depth o to 0.30 mm. 



Very indefinite absorption in green- 

 yellow, yellow, and orange, with 

 maximum in yellow. Absorption is 

 strong at 0.20/1 and decreases gradu- 

 ally to about 0.34/1. Approximately 

 transparent from 0.4/x to 0.5/1. Ab- 

 sorption starts near 0.50/r,, increases 

 to a maximum about 0.54/t, and de- 



52. Blue-Black Continued. 



creases to weak, general absorption 

 from 0.58/1 to 0.63/t. 



53. Anthracene Yellow C. (C.) Sodium 



salt of thio-di-benzene-disazo-di-sali- 

 cylic acid. 



Similar to fig. 37, pi. 10 ; No. 190, 

 S. & J. ' 



r>rownish-yellow powder. In solution 

 muddy yellowish brown, greenish 

 yellow. 



6 g. per liter (filtered). 



Angle 21.3'. Depth o to 0.18 mm. 



Absorption in violet. Somewhat sim- 

 ilar absorption to that of solution 

 No. 81. However, the absorption of 

 solution No. 53 is more intense than 

 that of solution No. 81. Absorption 

 decreases from 0.20/1 to a semi-trans- 

 parent strip at about 0.295/1. Beyond 

 this strip a band with hazy contour 

 extends as far as 0.41/1 with its max- 

 imum at about 0.34/1. Transparent 

 from 0.4 i/i to 0.63/1. 



54. Bismarck Brown. (A.) Hydrochloride 



of benzene-disazo-phenylene-diamine. 

 Fig. 7, pi. 2 ; No. 197, S. & J. 

 Dark-brown powder. In solution brown, 



yellow. 

 30 g. per liter (filtered). 

 Angle 19.5'. Depth o to 0.18 mm. 

 Visible and photographic ab.sorption 



identical with that of solution No. 12. 



55. V e s u v i n e. (B.) Hydrochloride of 



toluene-disazo-Mj-tolylene-diamine. 



Fig. 7, pi. 2; No. 201, S. & J. 



Dark-brown powder. In solution red- 

 dish brown, yellow. 



4.29 g. per liter. 



Angle 31.2'. Depth o to 0.29 mm. 



Visible and photographic absorption 

 identical with that of solution No. 12. 



56. Congo Orange G. (A.) Sodium salt of 



diphenyl - disazo-phcnetol-/3-naphthyl- 

 amine-disulphonic acid. 



Fig'- 33, pl-9; No. 217, S. & J. 



Brownish-red powder. In solution red- 

 dish yellow, yellow. 



5.38 g. 'per liter. 



Angle 23.4'. Depth o to 0.21 mm. 



Hazy absorption in blue, blue-green, 

 and green with maximum in the 

 green. Tolerably strong absorption 

 decreases from 0.20/1 to a weak mini- 

 mum near 0.32/1 and then increases 

 to a maximum about 0.36/t. A 

 semi-transparent region lies between 



Spectrogram too indefinite for reproduction. 



