Intelligence  and  Miscellaneous  Articles.  47 
duced  by  placing  a  piece  of  ordinary  wire  gauze  on  the  ring  of  a 
retort  stand,  about  four  inches  above  a  Sugg's  steatite  pin-hole 
burner,  and  lighting  the  gas  above  the  gauze.  "  The  flame  is  a 
slender  cone  about  four  inches  high,  the  upper  portion  giving  a 
bright  yellow  light,  the  base  being  a  non-luminous  blue  flame.  At 
the  least  noise  this  flame  roars,  sinking  down  to  the  surface  of  the 
gauze,  becoming  at  the  same  time  almost  invisible.  It  is  very  active 
in  its  responses ;  and  being  rather  a  noisy  flame,  its  sympathy  is  ap- 
parent to  the  ear  as  well  as  to  the  eye.5' 
A  simple  addition  to  this  apparatus  has  given  me  a  flame  which, 
by  slight  regulation,  may  be  made  either : — (1)  a  sensitive  flame 
merely,  that  is  a  flame  which  is  depressed  and  rendered  non-lumi- 
nous by  external  noises,  but  which  does  not  sing ;  (2)  a  continuously 
singing-flame,  not  disturbed  by  outward  noises ;  (3)  a  sensitive 
flame,  which  only  sounds  while  disturbed ;  or  (4)  a  flame  that  sings 
continuously,  except  when  agitated  by  external  sounds.  The  last 
two  results,  so  far  as  known  to  me,  are  novel. 
To  produce  them  it  is  only  necessary  to  cover  Barry's  flame  with 
a  moderately  large  tube,  resting  it  loosely  on  the  gauze.  A  luminous 
flame  six  to  eight  inches  long  is  thus  obtained,  which  is  very  sensi- 
tive, especially  to  high  and  sharp  sounds.  If  now  the  gauze  and 
tube  be  raised,  the  flame  gradually  shortens  and  appears  less  lumi- 
nous, until  at  last  it  becomes  violently  agitated,  and  sings  with  a 
loud  uniform  tone,  which  may  be  maintained  for  any  length  of  time. 
Under  these  conditions,  external  sounds  have  no  effect  upon  it.  The 
sensitive  musical  flame  is  produced  by  lowering  the  gauze  until  the 
singing  just  ceases.  It  is  in  this  position  that  the  flame  is  most 
remarkable.  At  the  slightest  sharp  sound  it  instantly  sings,  con- 
tinuing to  do  so  as  long  as  the  disturbing  cause  exists,  but  stopping 
at  once  with  it.  So  quick  are  the  responses,  that  by  rapping  the 
time  of  a  tune,  or  whistling  or  playing  it,  provided  the  tones  are 
high  enough,  the  flame  faithfully  sounds  at  every  note.  By  slightly 
raising  or  lowering  the  jet  the  flame  can  be  made  less  or  more  sen- 
sitive, so  that  a  hiss  in  any  part  of  the  room,  the  rattling  of  keys, 
even  in  the  pocket,  turning  on  the  water  at  the  hydrant,  folding  up 
a  piece  of  paper,  or  even  moving  the  hand  over  the  table,  will  excite 
the  sound.  On  pronouncing  the  word  "  sensitive"  it  sings  twice  ; 
and  in  general  it  will  interrupt  the  speaker  at  almost  every  "  s  "  or 
other  hissing  sound. 
The  several  parts  of  the  apparatus  need  not  be  particularly  re- 
fined. By  the  kindness  of  Pres.  Morton  I  have  used  several  sensi- 
tive jets  of  the  ordinary  kind  made  of  brass  ;  they  all  give  excellent 
results.  Glass  tubes,  however,  drawn  out  until  the  internal  dia- 
meter is  between  one  sixteenth  and  one  thirty-second  of  an  inch,  will 
do  almost  equally  well.  For  producing  merely  the  singing-flame, 
even  the  inner  jet  of  a  good  Bunsen  burner  will  answer.  The  kind 
of  gauze  too  is  not  important :  I  have  generally  used  a  piece  which 
not  to  be  original  with  Mr.  Barry,  since  identically  the  same  thing,  apparently, 
was  described  months  earlier  by  Prof.  Govi,  of  Turin,  and  noticed  in  the  Sep- 
tember Number  of  the  '  Moniteur  Scientifique.' — Eds.  of  Am.  Jmtrn.] 
