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Transactions of the Royal Society of South Africa. 
4. ^-Methoxybenzaurine ( = aurine methyl ether) has A 551. 
5. Dimethylaminodioxyphenyldinaphthylcarbinol, from dimethyl- 
aminobenzaldehyd and a-naphthol, has A 730 when neutral and A 492 
when acid. 
6. 2-2 / -4-4'-tetraoxytriphenylcarbinol has A 516 (non-fluorescent). On 
heating with zinc chloride this gives resorcin-benzein, A 492 (very fluorescent). 
7. Paranitro-malachite green has A 642 in water. Formanek gives A 637 
in alcohol. The band is vague and not easily measured. 
8. Nitro-oxy-dimethylaminotriphenylcarbinol, from 4-nitro-4'-oxybenzo- 
phenone, has apparently A 610, whereas calculation gives A 575. This requires 
reinvestigation. 
9. Para-amino-malachite green (unsymm. tetramethylfuchsine), from 
reduction of No. 7, has A 581 in acetic acid, A 610 vague in stronger acid, 
and is yellow in HC1 (A about 420). 
10. 2-2 / -4-4'-4 // -pentaoxytriphenylcarbinol (dioxyaurine) has A 545. 
11. Unsymm. dimethyl parafuchsine, from dimethylaminobenzaldehyd 
and aniline hydrochloride, has AA 547 and 493 when neutral, but when acidic 
shows vague bands at about A 575 and near the red end (over A 700), which 
is surprising. 
E. Various Simple Coloured Substances. 
(a) Quinonoxime. This has two vague bands at both ends of the 
spectrum, viz. about AA 680 and 350. 
(b) Sodium salt of foregoing (Na-p-nitrosophenol). In water A 398. 
Baly gives A 415 in alcohol. 
(c) Nitrosodimethylaniline. The green base has A 415+ A 725. The 
acetate has A 457 alone : the chloride in HC1 A 390. 
(d) 2-3-dicyano-quinol. This is colourless, but with a very strong 
fluorescence : A about 330 neutral, A 410 alkaline. The fluorescence of the 
salts of this substance is extraordinary, so that this is probably the simplest 
highly fluorescent substance. 
(e) 3-6-dioxyphthalimide (from hydrolysis of above). This is yellow 
with A 405 when neutral, but A 480 in NaOH : highly fluorescent. 
(/) 3-6-dioxyphthalic acid. When neutral this is nearly colourless with 
A 370. Alkali turns it yellow (A 437) with a marvellous fluorescence. The 
fluorescence must depend on the juxtaposition of ONa and COONa, since I 
find that sodium salicylate, when examined in presence of NaOH in sunlight, 
shows a fluorescence (violet). 
F. Unclassifiable Observations. 
I. Quinizarine : chief band A 598. 
II. 2-chloroquinizarine : chief band A 601. 
