A HUMIDIKIKK POK LKMOX (M'KINO ROOMS. 3 



attempt to hold the relative humidity of several curing rooms at 

 about the following conditions, viz, TO per cent, 75 per cent, 80 per 

 cent, 85 per cent, 90 per cent, and 95 per cent. 



The rooms were kept tightly closed during the day and opened 

 at night, when the conditions of the outside atmosphere were such as 

 to make ventilation advisable, in order to assist in maintaining the 

 inside condition of humidity at the desired point. Owing to the ex- 

 treme fluctuation of the conditions of relative humidity in the out- 

 side atmosphere during the day and night and from day to day, 

 ventilation alone was found to be impracticable as a means for main- 

 taining a uniform condition of humidity in the curing rooms. It 

 was found that excessive humidity in the rooms could be quickly 

 reduced by opening the ventilators during the day, when the dew 

 point of the outside air was much lower than that of the air inside the 

 rooms. The real difficulty was found to be that of increasing the 

 humidity in the curing rooms when it dropped below the condition 

 desired. 



METHODS TRIED FOR INCREASING THE RELATIVE HUMIDITY. 



Several methods were tried for adding to the humidity in the cur- 

 ing rooms. The ground under one of the curing rooms was sprinkled 

 with water. This method proved objectionable from the fact that 

 by its use molds which were injurious to the fruit began to develop. 

 Then a small perforated water pipe was arranged along the sides 

 of one room, near the top, with a valve to regulate the spray of 

 water from the pipes. This method was found to be inadequate. 

 Later, sacks of coarse, heavy cloth were suspended from these pipes 

 and the spray of water was allowed to fall on them. This method 

 Avas also found to be ineffective. 



A commercial humidifier used in tobacco warehouses was tried in 

 one of the rooms. This machine consists in part of a rapidly re- 

 volving fan which throws a fine spray of water into the room. For 

 the conditions in the lemon curing room this apparatus was found to 

 be impracticable and was finally discarded. Other somewhat similar 

 machines manufactured for the same purpose were used and found 

 to be of little or no value for this work. 



About this time the writer conceived the idea of increasing the 

 humidity of the curing rooms when necessary by the evaporation of 

 water from saturated cloths. Several ways of doing this were tried. 

 The first apparatus consisted of a shallow, galvanized-steel pan, 2 

 feet wide, 3 feet long, and 6 inches deep. Into this pan was set a 

 series of wooden frames, about 3 feet long and 1 foot high, spaced 

 about 2 inches apart. During several tests they were covered with 

 cotton and other absorptive cloths. The pan was nearly filled with 



