This section is from the book "Economical Cookery", by Marion Harris Neil. Also available from Amazon: Economical Cookery (1918).
Apples or peaches
Pare and core apples, then slice or cut them in quarters. They dry faster when sliced, as more surface is exposed. Steam pieces of apples three minutes. Now spread them on a drier and dry until leathery and tough, and when pressed between fingers no soft places can be detected. This requires, on a hot-air drier, on a good drying day, about three hours at 180° F. One peck of apples at one time may be dried on three oven racks.
This recipe will answer for peaches, apricots, and pears.
A hot-air drier is a commercial device, and hot-air drying can be recommended as the best method for drying fruits and vegetables. A slow oven may also be used for drying.
To Dry Pears. Pare, core, and slice pears into rings. To prevent discoloration, dip fruit as it is prepared into cold water with one ounce of salt to each gallon of water. Place in a colander and set over pan of hot water; place cover on pan and steam ten minutes. Dry fruit between clean towels or in sun, to remove surface moisture; spread on plates or trays and dry in sun, or in oven, over stove or before an electric fan until pears are tough and leathery. Stir from time to time, so they will dry evenly. Store in cloth or paper bags or in tight pasteboard boxes. All dried products should be examined occasionally, and upon the first appearance of insects they should be spread in thin layers in the sun until insects disappear, then heated to a temperature of 160° F. and stored again.