New York Agkicdltukal Experiment Station. 217 



trench may be dug narrower and one or two feet deeper and the 

 tile lolaced one above the other. The shaft for carrying the 

 funnel must be made tight; it may be 12 inches square, if made 

 of plank, or 12 inches in ^diameter, if made of galvanized iron. 

 The height should be sufficient to enable the funnel to catch the 

 wind readily. The construction and mounting of the funnel are 

 illustrated in Plate IX. The extreme diameter of the funnel 

 should be about 3G inches. 



The inlet from the sub-earth duct into the curing-room must 

 be provided with some arrangement of valves that will permit 

 the air to be shut off wholly or partly. Too rapid entrance of 

 air in warm weather will not permit enough cooling during pas- 

 sage through the duct. In case of dry winds, too rapid entrance 

 would reduce the moisture too much. 



In Plate X there is illustrated a deep vertical sub-earth duct. 

 Such a duct has the advantage of requiring less piping and also 

 less wind will suffice to produce a current of air. The vertical 

 duct should have a depth of not less than twenty-five or thirty 

 feet, provided water is far enough from the surface. Thirteen 

 lines of 6-inch drain or 5-inch galvanized iron conductor pipe 

 may be used and placed as in the cut. The duct should be 

 located near the north end of the curing-room or directly 

 beneath it. A hanging platform can be used in placing the 

 pipes or tubes in position and the earth packed carefully around 

 the pipes. An excavation of proper size, made as for an 

 ordinary well, will answer the purpose. After the duct has 

 been placed in position the earth that has been removed can be 

 used for filling around the duct. 



In Plate XI there is represented a duct connected with a well 

 of water. In the particular instance illustrated, the well is 64 

 feet deep; the intake pipe is 10 inches in diameter, rising just 

 barely above the roof of the factory, entering the well, as shown 

 at A, two feet below the surface of the ground and then descend- 

 ing inside the well a distance of 8 feet. Another 10-inch gal- 

 vanized iron pipe starts 40 feet below the surface of the ground 

 and rises to within 5 feet of it, when it turns and passes hori- 



