46  GAS  FURNACE  FOR  GENERAL  CHEMICAL  USE. 
DESCRIPTION  OF  A  GAS  FURNACE  FOR  GENERAL  CHEMICAL 
USE. 
By  John  Joseph  Griffin,  F.  C.  S. 
I  have  already  published  descriptions  of  several  gas  furnaces, 
adapted  to  special  purposes.  The  present  notice  refers  to  a 
simple  form  of  gas-burner,  which,  aided  by  suitable  fittings,  can 
be  used  as  a  convenient  source  of  heat  for  most  operations  of 
the  chemical  laboratory  and  lecture  table.  It  will  boil  a  quantity 
of  liquid,  exceeding  two  gallons  at  once;  it  will  raise  a  4f  inch 
fire-clay  crucible  to  full  redness;  it  will  fuse  anhydrous  carbon- 
ate of  soda  in  greater  quantity  than  is  required  for  the  analysis 
of  a  siliceous  mineral ;  and  it  will  melt  small  quantities  of  ster- 
ling silver.  This  amount  of  power  is  sufficient  for  most  chemical 
operations  that  are  not  metallurgic. 
The  Gas  Burner. — Fig.  1  represents  the  gas  burner  of  this 
apparatus.  The  gas  is  supplied  by  the  horizontal  tube,  whence 
it  passes  through  a  set  of  small  holes  into  the  box  a,  in  which  it 
mixes  with  atmospheric  air  that  enters  freely  by  the  holes  shown 
