UNIVERSAL ASPECTS OF ATMOSPHERIC ELECTRICITY Lil 
JULY 9, 1937 
JULY 8, 1937 75° WEST MERIDIAN HOURS : 
l2 
i, I nat ii ! 
Wt LOT 
11) HHH Mt i| MM HII 
| i nt mame sonar adam dod dia 
| Hd | Hy 
ie AHI il lit ii i | 
| ane 
0 
VERTICAL SCALE IN CES oF 10-4 ESU 
| | 
Ha 
thi 
| 
HE 
i 
t 
EET | a (| 
VERTICAL SCALE IN VOLTS PER METER Oo ey 
Fic. 5.—Electrograms, Huancayo Magnetic Observatory, “quiet”’ day during dry season. 
_ FROM 1b a , - 7cs NOTE 0.02 
. MARCH 17, 1937» : oe - ARCH 18, 1937 
75° WEST MERIDIAN HOURS 
8 
: ni ip 
mi f dams 
VERTICAL SCALE IN UNITS OF 1074 ESU 
QT TET 
| it 
VERTICAL SCALE IN UNITS OF 10% ESU PP? 
| 
t 
|POTENTIAL GRADIENT 
Fic. 6—Hlectrograms, Huancayo Magnetic Observatory, rainy day. (Note: Clearing in morning alter 10. 54; early acromicgd 
March 18, increasing cloudiness, distant rain, and thunder to southwest at 14.) 
eates that the electric charge of the dust in this whirl- Watheroo Magnetic Observatory, are illustrated in Fig. 
wind is preponderantly negative. 3. This effect, apparently of type (a), is clearly cor- 
The relatively small and rapid variations of electric related with wind strength and wind variability. Pre- 
field, which are common during daytime at the sumably the fine sand, prevalent in this semiarid region 
