441 
GASES BY THE ACTION 
OF BONTGEN BAYS AND 
OTHEB AGENTS. 
Discharge from Pointed Platinum Wire in Air. 
expansion. 
Terminals joined hy a wire before 
Gauge reading (in 
millims.) = 
1 Interval ).)efore ex- 
' pansion. 
Sign of chai’ge on 
wire. 
Besult of expansion. 
75 
75 
75 
40 sec.s. 
10 ,, 
5 mins. 
Negative 
n 
Slight shower 
Slight fog 
26 
90 secs. 
Negative 
0 
55 
30 secs. 
Negative 
Fog 
55 
20 „ 
Slight fog 
55 
60 „ 
^ 5 
Shower 
45 
30 secs. 
Negative 
Very few drops 
45 
10 „ 
0 
45 
60 ,, 
Very few drops 
87 
10 secs. 
Negative 
Veiy few drops 
87 
30 „ 
Fog 
87 
10 ., 
Positive 
Slight fog 
87 
0 
0 
87 
30 „ ' 
« 1 
Slight fog : 
104 
2 secs. 
Negative 
0 
104 
30 „ 
11 
Fog 
104 
60 „ 
Fog 
104 
2 mins. 
1^ 
Slight fog 
104 
6 ., 
11 
1 or two fh‘o]rs 
170 
15 secs. 
N egative 
Very dense fog 
170 
2 mins. 
Slight fog 
170 
15 secs. 
I’ositive 
Dense fog 
170 
70 „ 
11 
Slight fog 
In the second column of the above table is given the time which elapsed from the 
moment when the discharge was sto|)ped till tlie expansion was made to take place. 
It w4]l be observed that, as this interval is increased, the expansion required to 
produce a fog diminishes; in other words, the nuclei appear to grow when left to 
themselves. In no case was fog detained with a pressure fall of less tlian 4 or 
5 centims. 
The nuclei produced by the discharge last for one or two minutes (whether the 
ware is positive or negative) ; during this time the number has diminished consider¬ 
ably, and practically none last so long as six minutes. 
VOL. OXCIl.—A. 3 L 
