FKUCTUiS LlMOMfck 117 



to one of us by HofFmami, darkens when it is shaken with alcoholic per- 

 chloride of iron, and turns dingy blackish brown when gently warmed 

 with the latter. 



Hesperctin forms crystals melting at 223° C, soluble both in alcohol 

 or ether, not in water ; they taste sweet. They are split up by potash 

 in Phloroglucin and Hesperetic acid, C'"H'"0\ 



On addition of feiTic chloride, thin slices of the peel are darkened, 

 owing probably to some derivative of hesperidin, or to hesperidin 

 itself. 



The name hesperidin had also been applied to yellow crystals 

 extracted from the shaddock, Citrus decumaiia L., the dried flowers of 

 which afford about 2 per cent, of that substance. It is, as shown in 

 1879 by E. Hoffmann, quite different from hesperidin as described above; 

 he calls it Nariii gin and assigns to it the formula C^H"'*'0*^+40H*. 

 Naringin is readily soluble in hot water or in alcohol, not in ether or 

 chloroform. Its solutions turn brown red on addition of ferric 

 chloride. 



Lemon juice, some of the characters of which have been already 

 noticed, is an important article in a dietetic point of view, being largely 

 consumed on shipboard for the prevention of scurvy. In addition to 

 citric acid it contains 3 to 4 per cent, of gum and sugar, and 2"28 per 

 cent, of inorganic salts, of which according to Stoddart only a minute 

 proportion is potash. Cossa^ on the other hand, who has recently 

 studied the products of the lemon tree with much care, has found that 

 the ash of dried lemon juice contains 54 per cent, of potash, besides 15 

 per cent, of phosphoric acid. 



Stoddart has pointed out the remarkable tendency of citric acid to 

 undergo decomposition," and has proved that in lemons kept from 

 February to July this acid generally decreases in quantity, at first 

 slowly, but afterwards rapidly, until at the end of the period it entirely 

 ceases to exist, having been all split up into glucose and carbonic acid. 

 At the same time the sp. gr. of the juice was found to have undergone 

 but slight diminution : — thus it was 1044 in February, 1-041 in Slay, 

 and 1027 in July, and the fruit had hardly altered in appearance. 

 Lemon juice may with some precautions be kept unimpaired for months 

 or even years. Yet it is capable of undergoing fermentation by reason 

 of the sugar, gum, and albuminoid matters which it contains. 



Commerce — Lemons are chiefly imported from Sicily, to a smaller 

 extent from the Riviera of Genoa and from Spain. From the published 

 statistics of trade, in which lemons are classed together with oranges 

 under one head, it appears that these fruits are being imported in 

 increasing quantities. The value of the shipments to the United King- 

 dom in 1872 (largely exceeding those of any previous year) was 

 £1,154,270. Of this sum, £986,796 represents the value of the oranges 

 and lemons imported from Spain, Portugal, the Canary Islands and 

 Azores; £155,330 the shipments of the same fruit from Italy; and 

 £3,825 those from Malta. 



Of concentrated lemon juice there were exported in 1877 from 

 Messina 1,631,332 kilogrammes, valued at 2,446,996 lire. The value of 



' GazetUi Chimica Italiana, ii. (1872) 385 ; added to lemon juice, oxalic acid may be 

 Journ. ofChem. Soc. xi. (1873) 402. detected in the mixture after a few days, is 



- Stoddart's statement that if potash be not supported by our observations. 



