134 THE RAISIN INDUSTRY. 



as its raisin centers are concerned, more elevated, or from one thousand 

 to two thousand feet or more. The nearness to the sea has there also 

 some influence to retard the maturing of the grapes, and it is certain 

 that in Southern California the later ripening of the raisin grapes is 

 principally due to this cause. Thus the picking in Riverside com- 

 mences between the loth and the 3oth of September, and while the 

 other raisin districts in the southern part of California may vary some, 

 still the ripening season coincides very nearly with that of Riverside. 

 In Highlands the grapes are said to ripen two weeks later than at 

 Riverside. In El Cajon the grapes ripen between the ist and loth of 

 September. In Fresno the Muscatel raisin grapes ripen in the end 

 of August, and generally by the 2Oth of August the picking has 

 begun everywhere on the drier soils, while on the wet soils it is gen- 

 erally retarded from one to two weeks. As a rule the dryness of the 

 soil influences considerably the ripening of the grapes, and even the 

 quality of the soil is not without some influence, as on sandy, warm 

 soil grapes ripen much earlier than on heavy land. As an illustra- 

 tion of such early ripening, we may mention that, on certain gravelly 

 soils northwest or north of Santa Ana, the Muscat grapes ripen two 

 weeks earlier than on the heavier and finer soils in the immediate 

 vicinity. The growers take advantage of this early ripening to sell 

 their Muscat grapes fresh instead of drying them. 



In Salt river and Gila valleys in Arizona the grapes are said to ripen 

 much earlier than in California, but so far the vineyards there are not 

 old enough to have been greatly benefited by this early ripening. On 

 the plains of Kern county the ripening is hastened by the nature of 

 the soil, and possibly also by the nearness to the desert and the desert 

 wind, by the greater distance from the sea, and by a less amount of 

 rainfall. In Malaga the grapes ripen several weeks earlier than in 

 Fresno; in fact, the whole Mediterranean region seems to be earlier 

 than California. As a general rule, we may state that the Muscat 

 grapes ripen later in Southern California than in the central portion 

 of the State. In regard to Sacramento and San Joaquin valleys, the 

 farther we go towards the south the earlier do the grapes ripen. 

 But in every district there are localities which are earlier than others. 

 The Muscat and Muscatel ripen earlier than the Sultana, which latter 

 grape begins to ripen earlier than the Muscat, but attains perfection 

 much later than any other of our raisin grapes. Thompson Seedless 

 ripens in Yolo about August loth, and is thus our earliest raisin grape. 

 Signs of Maturity. There are three different ways by which the 



M ripeness of a grape can be tested, saccharometer, taste or color. The 



saccharometer is a well-known instrument, consisting of a graded glass 



V tube that will sink to different depths in liquors containing different 



percentages of sugar. There are different kinds of saccharometers, 



but the most practical one for the general raisin-grower is one 



divided in one hundred degrees, each degree showing one per cent of 



sugar to every hundred of water. Thus, if the saccharometer sinks 



down to twenty-five, we know that the water or must contains twenty- 



/ five per cent of saccharine water and seventy-five per cent of water. 



\J To properly test the grapes, a few bunches should be picked from 



