44 



ATLAS OF ABSORPTION SPECTRA. 



134. Alizarine Orange. (Powder 80 per 



cent.) (M.) 



Fig. 24, pi. 6. 



Very deep-purple powder. In solution 

 dark red, red. 



5.83 g. per liter (warmed and filtered). 



Angle 27.3'. Depth o to 0.25 mm. 



Weak, shadowy band in the green-yel- 

 low, gradually fading away in the 

 red. The ultra-violet absorption is 

 intense and one-sided, and ceases 

 about 0.39/ix. The visible band be- 

 gins near 0.48/x, has its maximum at 

 0.52S/X, and fades into general ab- 

 sorption about 0.56/x. The end of 

 the negative slopes to an unusual 

 extent, showing that the general ab- 

 sorption is relatively strong. 



135. Alizarine Red No. i. 40 per cent. (M.) 

 Similar to fig. 11, pi. 3. 



Yellow paste. In solution deep yel- 

 low, yellow. 



Saturated. 



Angle 31.2'. Depth o to 0.29 mm. 



Absorption very weak, general, and in- 

 definite. A few mm. of the solution 

 show complete opacity. The solu- 

 tion looks like a milky but yellow 

 enuilsion. The ultra-violet absorp- 

 tion is relatively weak, is quite gen- 

 eral, and fades away to semi-trans- 

 parency near o.4fi. A slight weak- 

 ening of transparency around 0.52/x 

 may be the fault of the sensitized 

 film. The end of the negative slopes 

 (|uite enough to indicate continued 

 absorption in the orange. No visible 

 absorption in the red. 



136. Aurophosphine 4 G. (A.) 

 Fig. 45. pi. 12. 



Keddish-brown powder. In solution 

 clear yellow, 3'ellow. 



1 1.67 g. per liter. 



Angle 27.3'. Dejith o to 0.25 mm. 



Strong absorption in the violet and 

 indigo. Absorption decreases from 

 0.20^ to a maximum at 0.245/* and 

 then follows a rounded curve to 

 transparency at 0.305/1. Unusual 

 transparency from 0.305/t to 0.390/1. 

 As for /"-nitrosodimethyl aniline, so 

 here, all the strong lines between 

 0.324/1 and 0.363/1 are transmitted 

 with almost no decrease of inten- 

 sity. A V-shapcd band absorbs 

 from 0.390/1 to 0.470/A with its max- 



136. Aurophosphine 4 G Continued. 



imum at 0.430/t. Transparent from 

 0.470/4 to 0.63/1. 



137. Brilliant Croceine, blue shade. (M.) 

 Similar to fig. 52, pi. 13. 

 Bright-red powder. In solution red, 



salmon pink. 



7 g. per liter. 



Angle 25.4'. Depth o to 0.23 mm. 



Strong band in blue-green and green. 

 It slopes more on the blue than on 

 the yellow border. Similar absorp- 

 tion to that of solutions Nos. 21 and 

 43. Absorption decreases from 0.20/x 

 to a region of partial transparency 

 in the vicinity of 0.29/1. A sym- 

 metrical, hazy band absorbs from 

 about 0.305/1 to 0.385/1. A strong 

 band absorbs from 0.458/1 to 0.558/1, 

 with its maximum near 0.518/1. 

 Transparent to the orange and red. 



138. Brilliant Purpurine 10 B. (A.) 

 Similar to fig. 21, pi. 6. 

 Grayish-violet powder. In solution red, 



bluish red. 



5.83 g. per liter (warmed). 



Angle 23.4'. Depth o to 0.21 mm. 



Shadowy band in the green with gen- 

 eral absorption in the yellow and 

 orange. Similar absorption to that 

 of solution No. 46. Absorption de- 

 creases from 0.20/1 to a semi-trans- 

 parent region around 0.29/t. A sym- 

 metrical, hazy band absorbs from 

 about 0.30/t to 0.38/1. Another band 

 begins near 0.48/t, has its maximum 

 at 052/1, and ends at 0.555/1. The 

 end of the negative slants at an 

 angle of about 30, thus emphasiz- 

 ing the strong, general absorption 

 in the yellow-orange. 



139. Carthamin. 



Similar to fig. 13, pi. 3. 



Reddish-brown plates. In solution 

 brownish red, faint brown. 



Concentrated. 



Angle 31.2'. Depth o to 0.29 mm. 



One-sided absorption in the ultra- 

 violet. Absorption similar to that 

 of solution No. 129. Absorption was 

 strong from 0.20/x to about 0.34/1. 

 From this wave-length on, the ab- 

 sorption curve is round and slopes 

 to o.445/t at the edge of the spec- 

 trogram farthest from the compari- 

 .son spectrum. Transparent from 

 0.445/1 to beyond 0.63/1. The slope 



