A'm'jJuiy?if9h3arm-}     The  Flash-Point  in  Mineral  Oils.  365 
burning  so  as  to  break  them.  I  had  the  lamp  half  filled  with  oil  and 
heated  to  certain  definite  temperatures.  At  50  above  the  flash- 
point (Abel)  all  in  general  went  out.  At  10°  above  flash  point  with 
some  low  flashing  (730  to  780),  petroleum  ignited  and  burned  vig- 
orously, and  some  merely  flashed  and  went  out.  High  flashing  oils 
(100°  to  110°  Abel),  10°  above  flash-point  invariably  went  out  or 
merely  flashed  ;  they  never  permanently  ignited.  At  150  above  the 
flash-point  the  high  flashing  oils  inflamed,  but  burned  quietly,  and 
the  fire  could  easily  have  been  commanded.  So  low  flashing  oils 
may  be  a  great  danger  if  overset  at  10°  above  flash-point ;  but  high 
flashing  oils  are  not  in  great  danger  until  150  over  flash-point  or 
more  ;  that  is,  if  overset  on  an  ordinary  floor.  If  overset  on  easily 
combustible  materials,  there  is  great  danger,  even  at  the  flash-point, 
and  as  the  absence  of  combustible  materials  cannot  be  depended  on, 
even  for  this  kind  of  accident,  the  flash-point  (Abel)  becomes  the 
point  of  danger.  If  an  open  cup  of  oil  heated  to  the  flash-point 
(Abel)  has  a  large  lighted  candle  plunged  into  it,  the  candle  is 
extinguished  just  as  by  water.  These  experiments  show  the  free- 
dom from  danger  in  lamp,  or  in  any  small  quantities,  and  particu- 
larly of  high  flashing  oil,  if  kept  several  degrees  under  the  Abel 
flash-point. 
High  flashing  oils  burn  practically  as  coolly  as  low  flashing  oils, 
and  if  we  seek  safety  by  using  a  high  flashing  oil  we  are  not  running 
into  any  other  danger. 
Coroner's  inquests  are  very  frequent  on  lamp  accidents.  It  has 
become  the  custom  for  the  inspectors  to  state  that  no  dangerous  oil 
is  now  imported  into  England,  and  inspector  and  coroner  put  the 
whole  blame  on  the  lamp.  But  surely  no  scientific  man  is  free  to 
state  that  73 0  flashing  oil  is  safe  in  our  climate.  It  is  often  8o°  or 
over  it  in  houses,  and  all  the  year  round  the  temperature  in  ordinary 
lamps  is  8o°  to  900.  The  danger  is  not  a  mere  matter  of  opinion, 
but  an  easily  ascertainable  scientific  fact ;  and  when  a  scientific  man 
makes  such  a  statement  regarding  a  matter  involving  hundreds  of 
deaths  in  England  every  year,  I  think  he  should  somehow  be  amen- 
able to  the  ban  of  the  profession,  if  to  nothing  else.  It  is  absurd 
to  condemn  the  poor  for  not  having  safety  lamps ;  besides,  even 
if  they  had  them,  they  are  only  an  extra  source  of  danger,  unless 
in  proper  order,  and  with  cheap  lamps  and  ignorant  people  tr  it 
could  not  be  depended  on. 
