Keegan: The Chemistry of the Lakeland Trees. 187 
chemical constituents are generally similar, but with some very 
decided differences. For instance, instead of, or perhaps in 
addition to, the inert and not very clearly defined bitter 
principle of the Wild eae we have in nearly all parts of 
the Mountain Ash, ery powerful and distinctively marked 
nitrogenous hiboude pets amygdalin, C*H*NO", which is 
easily resolved by the ferment emulsin into glucose, oil of 
bitter almonds, and prussic acid. Then again, in lieu of the 
inert and feeble fruits of the foregoing, we have in the Rowan 
Berry a veritable curiosity, an extraordinary phenomenon indeed 
in the chemistry of plants. With some exceptions, the whole 
battery, so to speak, of the vegetable chemical constituents 
seems to be represented here. Before becoming rose-red they 
contain tartaric acid; when still unripe they contain a large 
quantity of malic acid, a white wax, resin, a volatile resin-acid, 
(parasorbic acid), a substance that yields propylamine on 
decomposition, also raed a and emulsin, an amorphous 
tannin and phlobaphene, glucose, mannite, and another alco- 
holic sugar called sorbitol, CoHMGS: ; the brilliant coral-red pig- 
ment of the epicarp is due to a mixture of carotin, anthocyan, 
and phlobaphene, but it is undoubtedly the carotin that 
is ty effective in causing it to ‘outshine spring’s richest 
blossoms 
‘Sycamore. Acer pseudo-platanus. This is perhaps more 
associated with home and humanity than any other tree in the 
district. ‘It has long been the favourite of the cottagers,’ says 
‘Wordsworth, ‘and with the Fir has been chosen to screen their 
dwellings.’ Science completely justifies the motion; for apart 
from the purely physical ambushment of its exceptionally 
strong ‘spray,’ the mystical entanglement of its boughs, and 
the remarkable denseness of its foliage, in point of fact, I know 
of no other leaf that is so richly charged with ‘warm and com- 
fortable’ fatty oil. Want of space forbids me to say more 
than that the eaesiea constituents of this powerful organism 
approach very near to that of its congener the Horse-Chestnut, 
but in lieu of the magnificently fluorescent zsculin of the latter, 
there seems to exist in the bark of this species a resinous bitter 
principle (apparently a saponin), with very distinct reactions 
towards acids, bromine, etc. he tannins and resins seem to 
be nearly identical, but in neither case is there that saturation of 
the wood with these bodies and their decomposition products 
which would suffice to render it eminently durable and valuable 
as timber. 
June 1898, 1808. 
