454 
ANALYSIS  OF  PENNSYLVANIA  PETROLEUM. 
of  gravities,  without  any  purification,  was  tested  as  to  its  burn- 
ing in  a  flat  wick  lamp.    At  the  commencement  of  the  trial,  it 
burnt  with  a  full  long  flame,  but  in  the  course  of  a  very  short 
time  it  gradually  commenced  to  grow  smaller,  and  in  the  course 
of  an  hour  it  '.iminished  to  about  one-third,  the  wick  very  much 
clogged  with  deposits  of  carbon,  and  giving  but  a  feeble  red 
light — this  trial  proving  very  unsatisfactory.    The  oil  was  sub- 
mitted to  further  treatment,  with  the  view  of  removing  from  it 
any  or  all  substances  that  might  interfere  with  the  proper  com- 
bustion of  it ;  to  this  end  the  oil  was  re-distilled  over  lime,  and 
then  treated  with  concentrated  sulphuric  acid  and  alkali.  The 
product  after  this  treatment  was  almost  colorless,  and  the  greater 
portion  of  its  original  odor  gone.    This  again  was  tested  in  the 
lamp,  as  in  the  first  instance.    The  commencement  of  the  com- 
bustion was  all  that  could  be  desired,  but  the  extent  of  flame 
rapidly  decreased,  and  at  the  end  of  an  hour  the  flame  had  fal- 
len oft"  to  not  more  than  a  third  of  its  original  size.    The  only 
difference  observable  between  it  and  the  former  trial,  was  the 
absence  of  carbon  deposited  upon  the  wick.    One  thing  is  ob- 
servable during  the  combustion  of  this  fluid,  that  the  wick  is 
rapidly  consumed,  and  to  throw  the  same  extent  of  flame  as  ob- 
tained from  coal  oil,  a  much  greater  elevation  of  it  is  required. 
That  the  cause  of  the  rapidly  diminishing  flame  is  from  the 
shortening  of  the  wick,  is  very  obvious,  as  a  tolerable  extent  of 
flame  may  be  kept  up  by  elevating  the  wick  as  the  flame  dimi- 
nishes, which  in  domestic  use,  would  be  very  troublesome  and 
inconvenient. 
The  product  from  this  specimen  of  petroleum,  it  will  be  seen 
from  the  above,  is  not  in  every  respect  a  good  burning  fluid,  as 
it  does  not  give  a  constant  flame,  and  rapidly  burns  away  the 
wick,  rendering  frequent  trimming  and  elevation  of  it  necessary, 
to  obtain  a  good  illumination  from  it,which  is  a  peculiarity  difficult 
to  account  for.  My  impression  is,  that  it  arises  from  a  defi- 
ciency of  carbon,  and  think  that  an  ultimate  analysis  would  de- 
monstrate that  it  contains  a  smaller  per  cent,  of  carbon  than 
coal  oil,  or  products  obtained  from  petroleum,  having  a  higher 
specific  gravity.  Such  has  been  my  experience  in  regard  to  pe- 
troleum, i.  e.,  the  higher  the  gravity  of  the  crude  material,  the 
more  valuable  the  products  both  for  the  purposes  of  illumination 
and  lubrication. 
