relating to Atmospherical Electricity. 
241 
Days. 
Wind. 
Barom. 
Ther. 
Sparks. 
Pos. 
Neg. 
Sept. 20 
w 
Inches. 
29.7° 
0 
57 
strong 
pos. 
when I left it last night. The weather 
this day has been nearly the same with 
that ot the preceding one ; only the fog 
began later, and continued longer. The 
rod has been electrified all this day. 
Near six o’clock A.M. I found the rod 
21 
NW 
2Q.QO 
58 
0 
neg. 
electrified, but very weak, barely suf- 
ficient to indicate the kind, and it re- 
mained so till near three o'clock P.M. 
The pith balls now closed (which I 
suppose has not happened before dur- 
ing the space of 92 hours) and opened 
negative. A heavy cloud from the 
NNW now approaches the rod, and a 
little rain falls, by which the rod is 
highly electrified negatively, and the bell 
rings briskly ; the pith balls diverge to 
their utmost limit, and exhibit their 
waving pendulous motion. These ope- 
rations took up about one hour ; and 
the rod continued electrified negatively 
the rest of the day. 
By the night bottle. The electricity in 
22 
w 
30.20 
5 2 
small 
pos. 
___ 
the rod barely sensible. 
The pith balls have not closed this day. 
23 
s 
29.95 
5 2 
small 
,pos. 
__ 
The weather serene. 
This morning a quarter before six 
24 
N 
3 °- 3 ° 
58 
0 
pos. 
o’clock, 1 found the electric charge in 
the rod much weaker than when 1 left 
it last night ; which I afterwards found 
had been occasioned by a spider fixing 
its web from the rod to the wall of the 
house ; for when the web was removed, 
the intensity of the electrical charge 
was soon increased. 
\ Dark cloudy weather, and a strong 
25 
NW 
3 °- 3 ° 
58 
0 
pos. 
— 
/ wind. 
26 
NW 
3 °- 3 8 
55 
small 
pos. 
— 
Between six and seven o’clock this morn- 
ing, I found the pith balls quite closed ; 
nor would they even stick to my finger 
when I touched them. At this instant 
there was a visible dew spread over the 
ground in Hyde-Park : I examined it 
with my hand exploring - rod, and 
quickly charged an electrometer suffi- 
cient to ascertain the kind, which was 
positive. I now suspected my daily 
enemies the spiders ; I therefore went 
upon the roof of the house with my 
