from  Lightning  at  Purfleet.  o.  89 
refinance : for  when  the  refiftance  at  the  furface  of  the 
brafs  ball  was  at  laft  overcome  by  the  influence  the  point 
had  upon  the  charge,  the  explofion  took  place  imme- 
diately; and  that,  not  only  between  the  two  fubftitutes, 
but  alfo  between  the  end  of  the  lefs  fubftitute  and  the 
point. 
A cloud,  therefore,  that  happens  to  be  charged,  and 
within  the  ftriking  diftance  of  another  cloud  which  is 
not  charged,  and  alfo  equally  within  the  influence  of  a 
pointed  conductor,  mult  neceffarily  produce  fimilar  ef- 
fedts  with  thole  mentioned  in  the  thirty- fourth  experi 
ment. 
On  the  other  hand,  clouds  that  are  circumftanced  like 
thofe  above,  and  not  within  the  influence  of  a rounded 
condudtor,  will  pafs  quietly  over  fuch  a termination,  and 
without  any  explofion. 
Nor  can  any  one,  at  all  acquainted  with  fubjedts  of 
this  kind,  want  to  be  reminded,  how  far  the  effedts  of 
experiments,  made  within  the  limited  power  of  fuch  an 
apparatus,  muft  differ  in  degree  from  thofe  which  are 
exhibited  in  the  great  and  wonderful  phaenomena  of 
nature. 
If  I could  grant  to  thofe  who  objedt  to  the  motion 
employed  in  fome  of  thefe  experiments,  that  a cloud 
charged  with  lightning,  and  motionlefs,  may  impend 
4 
over 
