xiv 
Transactions of the Royal Society of South Africa. 
Tvhilst the bands of the ruby, although similar in arrangement, are displaced 
into a region of lower frequency. Both gem colours are due to chromium, but 
the vibrations are differently loaded (silica and beryllia against alumina). 
" Colour and Chemical Constitution. Part III : Derivatives of the 
imknown ortho-para-phenolphthalein." By James Moir. 
Phthaleins in which one of the hydroxyl-groups is ortho- and the other 
'jiara- to the central carbon have been prepared from para-substituted 
phenols Vv^ith oxybenzoylbenzoic acid. They are like the common phthaleins, 
but their absorption-bands are broad, although in much the same position. 
An attempt to make o-jj-phenolphthalein itself gave a product very closely 
resembling common phenolphthalein, and a similar substance was obtained 
by dehydrating oxybenzoylbenzoic acid alone with sulphuric acid. They 
are, nevertheless, probably not identical with common phenolphthalein. 
" Phenolphthaleinoxime " is not an oxime, but is the ^^-oxyanil of oxybenzo- 
phenonecarboxylic acid. Common phenolphthalein in normal alkali is 
colourless when cold, but becomes pink on warming. 
