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External  Preparations. 
Am.  Jour.  Ptaarm. 
June,  1903. 
but  not  through  the  skin,  and  thus  have  the  desired  effects  without 
producing  any  systemic  or  constitutional  results.  The  objection  to 
the  old-style  plasters  with  a  lead-plaster  vehicle,  that  they  are 
impaired  by  age,  become  brittle  and  lose  adhesiveness,  has  been  met 
by  improved  methods  of  manufacture,  affording  an  adhesive  plaster 
which  retains  its  flexibility  and  through  the  admixture  of  a  little 
rubber  adheres  without  being  artificially  warmed. 
For  diadermatic  or  systemic  effects  the  vehicle  for  plasters 
should  be  animal  fat,  such  as  lard  or  suet  with  waxes,  or  preferably 
mixtures  of  these  with  lanolin,  substantially  like  the  plaster-mulls  of 
Unna.  The  official  mercury  plasters,  at  present  made  with  lead 
plaster  and  gum  resins,  should  be  prepared  with  this  lanolin  vehicle. 
OLEATES. 
The  official  oleates  are  liquid  or  semi-solid  mixtures  of  the  respec- 
tive oleates  in  oleic  acid  in  excess,  which  renders  them  often  ineli- 
gible. The  true  oleates,  or  so-called  "  dry  oleates,"  are  preferable, 
but  these  should  be  diluted  with  a  proper  vehicle  before  use. 
As  indicated  above,  the  oleates  do  not  penetrate  through  the 
skin,  which  becomes  self-evident  when  the  constant  use  of  soap 
(sodium  oleate)  is  considered.  While  there  is  plenty  of  evidence 
that  the  natural  oleates,  the  oils  of  olive  and  almond,  also  the  oleo- 
palmitates  and  stearates,  lard,  butter,  etc.,  in  which  the  respective 
acids  are  linked  with  the  radical  glyceryl,  penetrate  through  the 
skin  and  are  absorbed  in  the  system,  the  artificial  compounds  of 
these  acids  with  the  metals  and  alkali  bases,  known  respectively 
also  as  insoluble  and  soluble  soaps,  are  not  absorbed  through 
external  use.  If  it  were  otherwise,  what  an  inducement  for  the  peo- 
ple in  "  the  farther  Mediterranean  "  to  consume  at  least  some  por- 
tion of  their  daily  rations  of  olive  oil  in  the  form  of  soap  ! 
LINIMENTS. 
The  value  of  liniments  depends  on  the  degree  they  penetrate  into 
and  through  the  skin,  only  one  official  liniment  being  protective, 
that  of  lime,  the  well-known  Carron  oil,  so  called  from  the  factory 
town  in  England  where  the  mixture  of  linseed  oil  and  lime  water 
originated  as  an  application  to  burns.  While  the  effects  resultant 
from  such  liniments  as  consist  of  oils  or  soap  solutions  are  supposed 
to  be  largely  influenced  by  the  mechanical  rubbing  or  massage  in 
