160 AMPELIDE^. 



or ovoid form, in which the cells are obliterated and some of the seeds 

 generally abortive. As the fruit is not articulated with the rachis or 

 the rachis with the branch, it does not drop at maturity but remains 

 attached to the plant, on which, provided there is sufficient solar heat, 

 it gradually withers and dries : such fruits are called Raisins of the sun. 

 Various methods are adopted to facilitate the drying of the fruit, such 

 as dipping the bunches in boiling water or in a lye of wood ashes, or 

 twisting or partially severing the stalk, — the effect of each operation 

 being to arrest or destroy the vitality of the tissues. The drying 

 is performed by exposure to the sun, sometimes supplemented by 

 artificial heat. 



The raisins commonly found in the shops are the produce of Spain 

 and Asia Minor, and are sold either in entire bunches or removed from 

 the stalk. The former kind, known as Muscatel Raisins and imported 

 from Malaga, are dried and packed with gi-eat care for use as a 

 dessert fruit. The latter kind, which includes the Valencixt Raisins of 

 Spain, and the Elemie, Chesme and stoneless Sultana Raisins of Smyrna, 

 are used for culinary purposes. For pharmacy, Valencia raisins are 

 generally employed. 



Microscopic Structure — The outer layer or skin of the berry is 

 made up of small tabular cells loaded with a reddish granular matter, 

 which on addition of an alcoholic solution of perchloride of iron assumes 

 a dingy green hue. The interior parenchyme exhibits large, thin-walled, 

 loose cells containing an abundance of crystals (bitartrate of potassium 

 and sugar). There are also some fibro-vascular bundles traversing the 

 tissue in no regular order. 



Chemical Composition — The pulp abounds in grape sugar and 

 cream of tartar, each of which in old raisins may be found crystallized 

 in nodular masses; it also contains gum and malic acid. The seeds 

 afford 15 to 18 per cent, of a bland fixed oil, which is occasionally 

 extracted. Fitz ^ has shown that it consists of the glycerides of Erucic 

 Acid, C^H*^0^, stearic acid, and palmitic acid, the first-named acid 

 largely prevailing. The crystals of erucic acid melt at 84° C; by means 

 of fused potash they may be resolved into arachic acid, C^.H*'0", and 

 acetic acid, C^H^O^. 



The seeds further contain 5 to 6 per cent, of tannic acid, which also 

 exists in the skin of the fruit. The latter is likewise the seat of 

 chlorophyll and other colouring matter. 



Commerce — The consumption of raisins in Great Britain is very 

 large and is increasing. The imports into the United Kingdom have 

 been as follows : — 



1870. 1871. 1872. 1876. 



365,418 427,056 617,418 583,860 cwt. 



val. £593,527, val. £707,344. val. £1,149,337. val. £1,058,406. 



Of the quantity mentioned for 1872 there were 400,570 cwt. shipped 

 from Spain, 176,500 cwt. from Asiatic Turkey, and the remainder from 

 other countries.^ It is stated that Greece, in 1874, exported about IJ 



^ Berichte der deutsch. chem. Geselhch. ^ Annual Statement of the Trade of the 



zu Berlin, iv. (1871) 442. United Khigdom. 



