from  Lightning  at  Purfleet.  283 
motion  was  rendered  fo  flow  as  feven  feet  feven  inches  in 
feven  feconds,  it  was  very  little  accelerated ; and  in  this 
ilate  the  great  cylinder  being  charged,  the  model  was 
fuffered  to  pafs : and  though  the  velocity  was  lefs  than 
three  quarters  of  a mile  in  an  hour,  the  point  was  ftruck. 
This  experiment  was  repeated  feveral  times,  with  the 
fame  fuccefs,  in  the  prefence  of  feveral  gentlemen. 
Having  made  two  other  experiments,  refpeCting  the 
different  terminations  of  conductors,  and  in  very  different 
circumflances  from  any  that  have  been  yet  related,  I 
fliall  here  give  an  account  of  them. 
exp.  xxxn.  When  the  great  ball  of  the  lefs  fub- 
ftitute  was  placed  at  the  greateft  ftriking  diftance  from 
the  ball  at  the  end  of  the  great  cylinder,  I fixed  a needle 
into  the  under  fide  of  the  remote  end  of  the  lefs  fub- 
ftitute,  with  the  point  downwards : oppofite  to  this  point, 
and  upon  the  fame  ftand  defcribed  in  the  twenty-fecond 
experiment,  was  fixed  another  needle;  fo  that  the  two 
points  were  oppofed  to  each  other.  The  fpace  between 
them  was  varied  from  time  to  time,  in  order  to  find  the 
greateft  diftance  at  which  the  lower  one  could  be  ftruck. 
Upon  charging  the  great  cylinder  it  appeared,  that  the 
greateft  diftance  in  this  cafe  was  five  inches  and  a 
quarter. 
Vol.  LXVIIL  O o 
EXP. 
