10 
BULLETIX 494, r. S. DEPAETMEXT OF AGEICULTUEE. 
are very desirable during excessively hot weather. In view of the 
fact that the only attention needed other than that given the ordi- 
nary electric fan is to keep the upper pan filled with water, the 
operation of this humidifier is simple and practicable. 
RESULTS. 
The use of the humidifier described in this bulletin in lemon curing 
rooms for two seasons has demonstrated the possibility of maintain- 
ing a uniform condition of relative humidity in such rooms. The 
action of the hiunidifier is entirely safe, and there has been no injury 
to the fruit in the curing rooms in which it has been used. 
The maintenance of a uniform condition of humidity in the 
curing rooms has resulted in an improved curing of the fruits, as 
shown by the better color and texture of the rind, the green color and 
firm condition of the calyx, or "button," and the juiciness of the 
lemons, as compared with lemons cured in the ordinary way in the 
same building and at the same time. The best condition of humidity 
for the curing of lemons, as shown by these experiments, lies be- 
tween 80 and 90 per cent. AATiile the necessity for the use of the 
humidifier in curing rooms varies in accordance with the char- 
acteristic atmospheric conditions of different lemon-growing regions, 
it can be said safely that in order to maintain uniform conditions of 
humidity the use of humidifiers is advisable at some seasons of the 
year in all the lemon districts of southern California. The im- 
proved appearance and quality of one carload of the fruits held 
under uniform conditions of humidity through the use of the humid- 
ifier are likely to more than pay for the humidifier and its cost of 
operation for the entire year. 
SUMMARY. 
A humidifier for use in maintaining conditions of uniform 
humidity in lemon curing rooms was invented by the writer in 1914:. 
This humidifier was the outcome of a series of experiments for 
the purpose of controlling the conditions of humidity in lemon 
curing rooms. 
It has been satisfactorily and successfully used for two seasons 
for the purpose for which it was built, and also for improving the 
air conditions in living rooms in private houses and elsewhere in 
California. 
The arrangement and structure of the humidifier are described 
and illustrated in this paper. It need not cost, aside from the elec- 
tric fan. more than $25. 
The best condition of relative humidity for curing lemons, as de- 
termined by these experiments, lies between 80 and 90 per cent. 
