~ 297 
PAPERS ON PHYSICS 
Calculation t 
Absoluie humidity of outdoor air at 18.5° and 92% =1,062 grains per 
of A I 
An absolute humidity of 1.062 grains of indoor air at 70° =13.3% rela- 
tive humidity. 
Friday, December 25, 1914 
Vemperature Relative Humidity 9 11 Tr tshaO wie 
am. am. p.m. p.m. p.m 
Maximum, 15°....... Indoor Rel. Humid. ................ 38% 35% 35% 31% 28 %? 
Minimum, -1°......... Outdoor Rel. Humid, ............ 78% 64% 57% 62%712% 
Average, 7°............ Average Relative Humidity for the Day.................-.- 67 To 
Calculation 
Absolute humidity of outdoor air at 7° and 67% =.447 grains per 
eq. it. 
An absolute humidity of indoor air of .447 grains at 70°=5.6% rela- 
tive humidity. 
Saturday, December 26, 1914 
Temperature Relative Humidity 7 11 12 2:30 4:30 6:30 
ai) a.m. m1... (p.m!) pms) pam) 
Maximum, 14°........ Indoor Rel. Hum......... 34% 33% 33% 35% 30% 32% 
Minimum, -13°......Outdoor Rel. Hum. 74% 54% 53% 64% 68% 72% 
Average, .5°............ Average Relative Humidity for the Day................... 64% 
Calculation 
Absolute humidity of outdoor air at 5° and 64% =.376 grains per 
Cul uit: 
An absolute humidity of indoor air of .376 grains at 70° =4%— rela- 
tive humidity. 
Sunday, December 27, 1914. 
Temperature Relative Humidity 9 11:45 4 9:30 
am. am. p.m. p.m. 
Maximum, 27°........ Indoor Relative Humidity........ 33% 33% 33% 33% 
Minimum, 12°........ Outdoor Relative Humidity........ 80% 74% 78% 84% 
Average, 19.5°......./ Average Relative Humidity for the Day...................... 79 J 
Calculation 
Absolute humidity of ourdoor air at 19.5° and 79% =.954 grains per 
CU site 
An absolute humidity of .954 grains of indoor air at 70°=11.9% rela- 
tive humidity. 
Mondav. December 28. 1914 
Temperature Relative Humidity 8 :30 11 
a.m. a.m. 
Maximum, 28°........ Indoor Relative Humidity..............0..02...... 32% 33% 
Minimum, 23°........ Outdoor Relative Humidity... 82% 76% 
Average, 25.5°........ Average Relative Humidity for the Day.......000...... 79% 
Calculation 
Absolute humidity of outdoor air at 25.5° and 79% =1.253 grains per 
cn, ft. 
An absolute humidity of 1.253 grains of indoor air at 70% =15.7% rela- 
tive humidity. 
1. The humidifier ran dry at this point. The drop in temperature necessitated 
more heat and this produced more rapid evaporation. It was necessary to open the 
needle valve wider. 
