There are several ways of stacking. The flat-stacking is used principally when the raisins are very dry, and when it is of importance that no air should enter the trays. In flat-stacking, one tray is simply placed on the top of the other, and the circulation of air thus brought to a minimum. In rainy weather, however, the roof-stacking is to be preferred. Instead of placing one tray on the top of another, the trays are placed in two piles joining each other in such a way that the inner end of every tray overlaps the edge of the tray in the adjoining pile. This lifting up of one edge of the tray gives to the whole pile a roof-like appearance, and the angle in which the trays join together becomes steeper the higher the pile grows, until, at the height of three or four feet, the trays slant so much that the raisins cannot rest on them, but are in danger of sliding off, when, of course, the pile should not be made any higher. It takes several times longer to stack the trays in roof fashion than to simply pile them up flat. The advantage of roof-stacking is that it admits more air, and sheds the rain better. In damp weather the piles should not be covered on the sides for any length of time, as the raisins will then mold more rapidly. If, instead of joining two piles of trays, three piles are made to join, the center stack will be flat, while much air is admitted to the raisins. In this stacking the first two trays are placed flat on the ground at almost the distance of one tray. Another tray is made to rest on the inner edge of the lower trays and cover the intermediate space, and so on. This method gives twice as much air space between the trays as regular flat-stacking, and is to be recommended when the weather is damp. A combination of this last method and roof-stacking is used by some, every grower almost having his favorite way to stack. It must be remembered that in very rainy weather no kind of stacking will be of any value, while, when the showers are few and far between, stacking may save the crop. Stacking is especially valuable in conjunction with dryers, when protection during a few days only is all that is needed. One man can stack about five hundred trays an hour, and the regular picking gang can stack a whole vineyard in a few hours. Should the rain be very heavy and no dryer handy, it is of no use to try to save the crop after the mold has begun to make its appearance, and when the berries have begun to rot. It is then far better to dump the whole crop in the field rather than to spend time, money and anxiety on raisins which must in any case become a total loss.