262  Papers  relative  to  an  Accident 
only  charge  it  by  degrees;  but  when  a ltroke  is  taken 
from  it,  the  greateft  part  of  the  charge  by  far  is  at  that 
inftant  taken  out  of  it : and  therefore  we  are  conbantly 
under  the  neceffity  of  renewing  the  charge  before  fuch 
another  broke  can  be  taken. 
Befides,  thunder-clouds  from  their  nature,  and  a va- 
riety of  circumbances  accompanying  them,  never  affume 
the  fame  fliape  and  bze : neither  are  they  always  at  the 
fame  dibance  from  each  other.  And  yet  we  are  told, 
that  they  have  been  obferved  to  brike  from  one  to. 
another  at  different  dibances,  jub  as  they  happen  at  the 
time  to  be  circumbanced. 
For  all  thefe  reafons,  I thought  it  was  proper  to  make 
particular  experiments  in  different  cafes,  where  fome  of 
the  circumbances  varied.  And  becaufe  a bngle  cloud, 
after  it  hath  bruck  any  one  objeft,  fometimes  continues 
to  difcharge  vab  quantities  of  lightning,  I propofed  to 
begin  the  experiments  with  the  great  cylinder  only. 
exp.  xn.  The  model  (furnibied  with  the  wire  of  com- 
munication, and  with  the  longeb  pointed  conductor 
upon  it)  being  properly  placed  upon  the  long  frame,  and 
held  there  in  readinefs  to  be  drawn  forward  by  the  line 
and  weight  at  the  other  end;  the  great  cylinder  was 
charged  by  twenty  turns  of  the  wheel.  On  letting  go  the 
model,  and  almob  at  the  inbant  before  the  point  came 
i.  under 
