First, those in which trays of fruit are placed upon stationary ledges within a heated chamber; second, those in which the trays are raised and lowered by mechanical means toward or farther from the source of heat as the drying progresses; third, those in which the fruit is placed in imperforate steam jacketed pans. Many improvements, of course, have been made in detail of form, in ventilation, the supplying and regulating of heat and the moving of trays. The hermetically sealed glass or earthenware fruit jar, the lids of which can be screwed or locked down upon a rubber band, after the jar is filled and the small remainder of air drawn out by a convenient steam heater, now used by the million, is an illustration of the many useful modern contrivances in this line. _Sterilisation._--In preserving, the desirability of preventing disease and keeping foods in a pure state has developed in the last quarter of a century many devices by which the food is subjected to a steam heat in chambers, and, by devices operated from the outside, the cans or bottles are opened and shut while still within the steam-filled chamber. _Diastase._--By heating starchy matters with substances containing diastase, a partial transformation is effected, which will materially shorten and aid its digestion, and this fact has been largely made use of in the preparation of soluble foods, especially those designed for infants and invalids, such as malted milk and lactated food. _Milkers._--Invention has not only been exercised in the preservation and transportation of milk, but in the task of milking itself. Since 1860 inventors have been seeking patents for milkers, some having tubes operated by air-pumps, others on the same principle in which the vacuum is made to increase and decrease or pulsate, and others for machines in which the tubes are mechanically contracted by pressure plates. _Slaughtering._--Great improvements have been made in the slaughtering of animals, by which a great amount of its repulsiveness and the unhealthfulness of its surroundings have been removed. These improvements relate to the construction of proper buildings and appliances for the handling of the animals, the means for slaughtering, and modes of taking care of the meat and transporting the same. Villages, towns, and even many cities, are now relieved of the formerly unsavoury slaughter-houses, and the work is done from great centres of supply, where meats in every shape are prepared for food and shipment. It would be impossible in a bulky volume, much less in a single chapter, to satisfactorily enumerate those thousands of inventions which, taking hold of the food products of the earth, have spread them as a feast before the tribes of men. _Tobacco._--Some of the best inventive genius of the century has been exercised in providing for man’s comfort, not a food, but what he believes to be a solace.