« 
from  Lightning  at  Purfleet.  263 
-011(161'  the  center  of  the  cylinder,  it  was  fuddenly  ftruck 
with  the  matter  of  lightning,  and  frequently  fooner. 
The  lead:  diftance  of  the  point  from  the  great  cylinder, 
when  this  ftroke  happened,  meafured  nearly  five  inches. 
The  quantity  of  charge  that  remained  in  the  cylinder 
was  very  little  to  the  fenfe  of  feeling,  though  taken  im- 
mediately after  the  ftroke  happened. 
exp.  xiix.  On  putting  into  the  place  of  the  pointed 
conductor  one  of  the  fame  length,  that  was  rounded  at 
the  end,  and  without  any  other  change  of  circumftances, 
the  wheel  having  been  turned  the  fame  number  of  times,  • 
I fuffered  the  model  to  pafs : the  rounded  end,  in  this  ■ 
cafe,  was  not  ftruck.  However,  the  inftant  after  it  had: 
pafled,  the  quantity  of  the  charge  that  remained  in  the 
cylinder  was  taken  in  the  fame  manner  by  the  hand; 
on  the  doing  of  which,  the  fenfation  was  more  violent ' 
than  in  the  laft  experiment. 
fifth  observation.  From  the  two  laft  experiments' 
it  appears,  that  though  every  circumftance  was  the  fame, 
excepting  the  different  terminations  of  the  two  conduc- 
tors, yet  the  pointed  one  only  was  ftruck ; notwithftanding 
they  were  both  of  the  fame  length,  and  pafled  at  equal 
diftances  from  the  cylinder.  From  whence  we  collect, 
that  the  quantity  of  lightning  difcharged  from  the  great 
cylinder  into  the  point,  when  an  explofion  happened, 
was-.- 
