298 ILLINOIS ACADEMY OF SCIENCE 
Additional Facts 
Average outdoor temperature for the period =13.3° or 12° below normal. 
Average outdoor relative humidity (daytime only) =77%. 
Average indoor relative humidity (daytime only) =34.5% with maxi- 
mum of 45% and minimum of 28%. 
Average calculated indoor humidity for the period=9.3%. 
The windows on the west and north side were provided with storm 
windows and the inside windows did not frost over; the single windows 
were covered with frost and much ice accumulated at the bottom of each. 
The outside wall of one west room showed considerable moisture on Satur- 
day, December 26th. 
On Saturday, December 26th, about six gallons of water were evaporated 
by the humidifier. On the average, probably about four gallons were 
evaporated daily. The water in the humidifier boiled on several occasions 
and stood near the boiling point frequently. 
While the data given cover a period of nine days only, the humidifier 
has been in use for several years and I am confident that these data indi- 
cate correctly the usual operation of the plant when low temperature pre- 
vails. (Fig. 2). 
R 1. THT aie 
H mer id. Tenp. 
10 (a) an 700° 
90%-90°F 
=f a [As cnt gt 
HH a H He 
at Sunt 
| a potas 
i y I ! b ifn ie 
ie 
G0% - 80°F; 
H i 
70k - 70° eee 
He H sre bestest 
a ty 
ee tt a 
aa elle ih 
Sag eee eerie ei ea ee 
oe 
60%, - bo” 
a 
HE aa a ae 
a i 
ee ee pees Th ores ee 
ee 
a rain ut edt ie 
SCH 
cael 
ot a Men tee me Thur Fi. —. Sun. re 
Mec. 20) 21) 52). 23) 29) 26 De a ee ee 
Fig. 2. Graphs: Outdoor Relative Humidity. Room Tem- 
perature, constant at 68°. Indoor Relative Humidity. Aver- 
age Outdoor Temperature, Max. + Min. Calculated Indoor 
Humidity. 2 
