A*i£2i', fs73RM "}     Oosmolin  and  Paraffin  Ointment.  535 
crude  petroleum  so  as  to  remove  successively  the  gasolin,  benzin, 
burning  oils  and  the  lighter  machine  oils.  The  residuum  is  then  sub- 
jected to  still  greater  heat,  and  its  vapor  is  brought  into  contact  with 
a  jet  of  superheated  steam,  for  the  purpose  of  expelling  the  last  traces 
of  light  hydrocarbon.  After  this  it  is  still  further  purified  and  deo- 
dorized by  the  action  of  hot  animal  charcoal.  We  are  consequently 
forced  to  conclude  that  cosmolin  is  simply  impure  paraffin,  or  a  mix- 
ture of  paraffin  with  varying  proportions  of  the  heavy  oils  which  are 
nearest  allied  to  it.  These  oils  are  known  to  the  trade  as  paraffin  oil, 
neutral  oil,  lubricating  oil,  spindle  oil,  &c.  Although  the  manufac- 
turers claim  cosmolin  to  be  a  simple  body,  this  is  refuted  by  their  own 
statement,  namely,  that  they  furnish  this  one  simple  body  in  the  form 
of  cerate,  which  remains  firm  at  95°,  as  a  jelly  which  is  fluid  at  85°, 
and  also  as  a  liquid  which  is  still  fluid  at  32°. 
Taking  advantage  of  the  fact  that  paraffin  is  only  very  sparingly 
soluble  in  alcohol,  we  dissolved  cosmolin  in  ether  and  in  benzin,  from 
both  of  which  solutions  the  paraffin  was  readily  precipitated  by  the 
addition  of  alcohol.  Cosmolin  is  turned  dark  brown,  like  caramel, 
by  sulphuric  acid,  but  this  is  no  doubt  due  to  its  impurities.  Nitric 
acid  produces  no  reaction  in  the  cold,  but  when  heated  turns  it  yellow 
and  finally  orange  color.  Muriatic  acid  and  liquor  potassae  have  no 
effect  upon  it,  either  cold  or  hot.  All  of  these  tests  point  to  the  pres- 
ence of  paraffin. 
As  cosmolin  appears  to  possess  some  merits,  and  is  certainly  gain- 
ing favor  with  physicians,  it  would  be  desirable  to  contrive  a  formula 
for  its  preparation. 
With  this  object  in  view  a  number  of  experiments  were  instituted 
for  the  purpose  of  obtaining  a  combination  having  similar  physical 
and  chemical  properties.  The  substances  which  seemed  most  suitable 
•were  pure  paraffin,  and  the  so-called  neutral  oil,  of  the  best  quality, 
which  possesses  less  of  the  peculiar  coal  oil  smell  than  any  other  kind 
examined.  The  gravity  of  this  oil  is  32°  to  33°,  and  its  boiling  point 
is  somewhere  about  500°.  Coal  oil  dealers  claim  that  this  oil  is  free 
from  odor,  though  this  statement  is  only  relatively  true.  In  order  to 
deodorize  it  still  more,  it  was  percolated  through  hot  animal  charcoal. 
One  part  of  paraffin  was  melted  and  three  parts  of  the  oil,  prepared 
in  the  manner  described,  were  added  to  it.  This  compound,  a  sample 
of  which  is  presented  herewith,  has  the  same  behavior  towards  reagents 
as  cosmolin.    Like  this,  it  melts  at  about  95°,  does  not  evaporate  be- 
