Intelligence  and  Miscellaneous  Articles, 
77 
with  its  lower  surface  at  a  height  of  some  15,000  miles,  but  was 
connected  to  it,  as  is  usually  the  case,  by  three  or  four  vertical  co- 
lumns brighter  and  more  active  than  the  rest.  Lockyer  compares 
such  masses  to  a  banyan  grove.  In  length  it  measured  3'  45",  and 
in  elevation  about  2'  to  its  upper  surface  ;  that  is,  since  at  the  sun's 
distance  1"  equals  450  miles  nearly,  it  was  about  100,000  miles 
long  by  54,000  high. 
At  1 2h  30m,  when  I  was  called  away  for  a  few  minutes,  there  was 
no  indication  of  what  was  about  to  happen,  except  that  one  of  the 
connecting  stems  at  the  southern  extremity  of  the  cloud  had  grown 
considerably  brighter,  and  was  curiously  bent  to  one  side  ;  and  near 
the  base  of  another,  at  the  northern  end,  a  little  brilliant  lump  had 
developed  itself,  shaped  much  like  a  summer  thunder-head.  Fig.  1 
represents  the  prominence  at  this  time,  a  being  the  little  "  thunder- 
head"*. 
Fig.l. 
What  was  my  surprise,  then,  on  returning  in  less  than  half  an 
hour  (at  12h  55m),  to  find  that  in  the  mean  time  the  whole  thing  had 
been  literally  blown  to  shreds  by  some  inconceivable  uprush  from 
beneath.  In  place  of  the  quiet  cloud  I  had  left,  the  air,  if  I  may 
use  the  expression,  was  filled  with  flying  debris — amass  of  detached 
vertical  fusiform  filaments,  each  from  10"  to  30"  long  by  2"  or  3" 
wide,  brighter  and  closer  together  where  the  pillars  had  formerly 
stood,  and  rapidly  ascending. 
When  I  first  looked,  some  of  them  had  already  reached  a  height 
of  nearly  4'  (100,000  miles);  and  while  I  watched  them  they  rose 
with  a  motion  almost  perceptible  to  the  eye,  until  in  ten  minutes 
(lh  05m)  the  uppermost  were  more  than  200,000  miles  above  the 
solar  surface.  This  was  ascertained  by  careful  measurement;  the 
mean  of  three  closely  accordant  determinations  gave  7'  49"  as  the 
extreme  altitude  attained ;  and  I  am  particular  in  the  statement, 
because,  so  far  as  I  know,  chromospheric  matter  (red  hydrogen  in 
this  case)  has  never  before  been  observed  at  an  altitude  exceeding  5\ 
layer  of  hydrogen  and  other  gsses  which  surrounds  the  sun  to  a  depth  of 
about  7000  miles.     Of  this  the  prominences  are  mere  extensions.        ^ 
*  The  sketches  do  not  pretend  to  accuracy  of  detail,  except  the  fouKji ; 
the  three  rolls  in  that  are  nearlv  exact. 
