BY-PRODUCTS 365 



If the fruit is in quarters or is dried whole, it may be spread 

 somewhat deeper, since in these forms it does not pack down so 

 closely as when in slices, and hence the circulation of hot air 

 through it is not impeded if the depth is somewhat increased. 



The fruit is generally put on the floor of the kiln as fast as it is 

 sliced, and the fire is started in the furnace below as soon as the 

 floor is filled, or, in many cases, before it is entirely covered. 



Oiling the floors and racks. It is a common practice to treat the 

 floor of a kiln with tallow to prevent the fruit from sticking to it. 

 This is done every few days, or as often as conditions warrant. 

 Sometimes a mixture of equal parts of tallow and boiled linseed 

 oil is used for this purpose. 



At each filling of the racks, where these are used, the surface 

 of the wire netting is lightly wiped over with a cloth moistened in 

 lard. This prevents the fruit from sticking to the netting and 

 keeps it clean. 



Turning the fruit. When kiln driers are used, the fruit is 

 turned occasionally to prevent its burning or sticking to the floor 

 by remaining in contact with it too long, and to insure the most 

 uniform drying that is possible. The interval between turnings 

 varies with different operators, with the condition of the fruit, and 

 with the degree of heat maintained. For the first five or six hours 

 it is generally turned about every two hours, and more frequently 

 as the fruit becomes drier, until when nearly dry it may require 

 turning every half hour. 



The objects to be obtained by turning must be kept in mind. 

 The fruit should be examined from time to time and turned often 

 enough to prevent scorching or sticking and to insure uniform 

 drying. 



Heating apparatus. Satisfactory results are so dependent on 

 the heating apparatus that this becomes one of the most important 

 considerations with an evaporator. In the smaller types of evapo- 

 rators, where comparatively little is involved and the question of 

 fuel does not enter seriously into consideration, almost any small 

 stove commensurate with the size of the particular evaporator in 

 question may be used. In the kiln evaporators large furnaces 

 are now most commonly used. These are specially designed for 

 the purpose, and are provided with relatively large fire pots, 



