THE MONTHLY BULLETIN. 41 



relative humidity was uniformly high, heing 96 per cent on August 17th. 

 From August 5th to August 21st it ranged between 85 per cent as a 

 minimum and 96 per cent as a maximum. In 12 days out of the 30, 

 it wa.s 90 per cent or above, and during the remainder of the time it 

 was higher than has been usually considered to be the best condition 

 for the storage of lemons. 



At the time that the pears were placed in this room, some of the 

 same lot were placed in an adobe room of a dwelling house, where fruits 

 and vegetables are commonly kept temporarily for family use. 



The pears in the family storage room, where no attempt was made 

 to control either the conditions of temperature or relative humidity, 

 ropened perfectly and were eaten within a week, or by August 10th. 

 These pears turned in color from green to a golden-yellow, became soft, 

 and reached a prime "eating" condition. 



The pears in the lemon room remained hard and retained their green 

 color until the end of the experiment on September 3d. So far as the 

 observations of a number of interested persons went, some of them 

 experienced deciduous fruit growers, there was no apparent change in 

 the pears from the day they were placed in the lemon room on August 

 4th until they were taken out on September 30th, or a total storage 

 period of 30 days. 



From time to time, during this experiment, several of the pears were 

 taken out of the lemon room and placed in the kitchen and the living 

 room of a dwelling. Those remaining in the lemon room at the end 

 of the storage period were removed and held under similar conditions. 

 Within six or seven days from the date of withdrawal these pears 

 ripened perfectly, and their eating quality was as good as those ripened 

 iu the adobe room. 



It is almost unbelievable that pears can be held for 30 days at the 

 high temperatures recorded without ripening or deteriorating. While 

 no definite conclusions have been drawn as to the cause of this, both 

 Mr. Chase and the writer believe that the condition of high relative 

 humidity was a controlling factor in retarding the ripening of the pears. 



One of the reasons for reaching this belief has been the repeated 

 experience in the lemon-curing house of finding that the "buttons," 

 (the calyx) of lemons held under conditions of high relative humidity 

 retain their original green color and living condition even during very 

 long periods of storage. The extraordinary condition of calloused stems, 

 and the perfect preservation of the "buttons," and the superior com- 

 mercial quality of the fruit, in the case of the lemons stored under 

 uniform conditions of high relative humidity, tend to emphasize the 

 importance of the factor of relative humidity to the storage and ripening 

 of fruits. 



Further observations, similar in character to the ones discussed in 

 this paper, will be made during the summer of 1917 and continued 

 until some further light is thrown on the relation of different conditions 

 of relative humidity to the ripening and holding characteristics of fruits 

 held in storage. 



