The quality of the wine depends on the grape and the soil, which has been examined and analysed by competent chemists. Omitting minute and uninteresting particulars, the first class and the best is termed the _Albariza_; this whitish soil is composed of clay mixed with carbonate of lime and silex. The second sort is called _Barras_, and consists of sandy quartz, mixed with lime and oxide of iron. The third is the _Arenas_, being, as the name indicates, little better than sand, and is by far the most widely extended, especially about San Lucar, Rota, and the back of Arcos; it is the most productive, although the wine is generally coarse, thin, and ill-flavoured, and seldom improves after the third year: it forms the substratum of those inferior sherries which are largely exported to the discredit of the real article. The fourth class of soil is limited in extent, and is the _Bugeo_, or dark-brown loamy sand which occurs on the sides of rivulets and hillocks. The wine grown on it is poor and weak; yet all the inferior produces of these different districts are sold as sherry wines, to the great detriment of those really produced near Xerez itself, which do not amount to a fifth of the quantity exported. [Sidenote: VINES OF ANDALUCIA.] The varieties of the grape are far greater than those of the soil on which they are grown. Of more than a hundred different kinds, those called _Listan_ and _Palomina Blanca_ are the best. The increased demand for sherry, where the producing surface is limited, has led to the extirpation of many vines of an inferior kind, which have been replaced by new ones whose produce is of a larger and better quality. The _Pedro Ximenez_, or delicious sweet-tasted grape which is so celebrated, came originally from Madeira, and was planted on the Rhine, from whence about two centuries ago one Peter Simon brought it to Malaga, since when it has extended over the south of Spain. It is of this grape that the rich and luscious sweet wine called _Pajarete_ is made; a name which some have erroneously derived from _Pajaros_, the birds, who are wont to pick the ripest berries; but it was so called from the wine having been originally only made at Paxarete, a small spot near Xerez: it is now prepared everywhere, and thus the grapes are dried in the sun until they almost become raisins, and the syrop quite inspissated, after that they are pressed, and a little fine old wine and brandy is added. This wine is extremely costly, as it is much used in the rearing and maturation of young sherry wines.