232         DISINFECTANTS  IN  ARRESTING  CATTLE  PLAGUE. 
into  market  many  substitutes  for  carbolic  acid,  in  which  the 
valuable  agent  is  diluted  with  cheap  inert  bodies,  whilst  the 
price  charged,  in  some  cases,  is  higher  than  that  of  the  genuine 
article.  Specimens  of  two  such  substitutions,  called  cresyline 
and  carboline,  were  forwarded  to  the  Royal  Cattle  Plague  Com- 
mission for  approval,  "  as  being  more  certain  disinfectants  than 
most  of  the  carbolic  acids  now  being  sold  to  the  public,  many  of 
which  contain  but  a  very  small  percentage  'of  that  acid."  It 
was  stated  that  the  preparations  contained  over  60  per  cent,  of 
carbolic  acid,  and  were  miscible  with  water.  As  it  was  possible 
from  these  and  other  reputed  advantages  that  the  preparations 
might  be  of  considerable  value,  they  were  forwarded  to  me  for 
examination.  Cresyline  consists  of  alkaline  water,  and  tar  oils 
boiling  above  370°  C,  therefore  containing  little  or  no  carbolic 
or  cresylic  acid.  Carboline  is  a  dilute  solution  of  caustic  soda, 
containing  4*1  per  cent,  of  carbolic  acid.  The  price  of  these  pre- 
parations is  higher  than  that  ordinarily  charged  for  good  com- 
mercial carbolic  and  cresylic  acids. 
Other  creosote  samples  from  different  makers  were  found  to 
contain  respectively  4*5,  2-6,  5*9,  and  4*2  per  cent,  of  carbolic 
acid,  the  rest  being  tar  oils.  In  other  instances,  articles  have 
been  sold  as  commercially  pure  carbolic  acid  which  were  found 
to  contain  from  30  to  50  per  cent.  Frequently  a  very  foetid 
sulphur  compound  is  allowed  to  remain.  This  should  be  avoided, 
as  although  the  antiseptic  powers  of  the  liquid  are  great,  the 
offensive  odor  which  it  diffuses  round  the  neighborhood  is  ex- 
cessively nauseous. 
48.  It  is  by  no  means  difficult  to  detect  the  adulterations  re- 
ferred to  above.  Commercial  carbolic  acid  is  soluble  in  from  20 
to  70  parts  of  water,  or  in  twice  its  bulk  of  a  solution  of  caustic 
soda,  while  oil  of  tar  is  nearly  insoluble  ;  but  if  the  amount  of 
carbolic  acid  be  increased  some  remains  undissolved. 
To  apply  the  tests  : — 1.  Put  a  teaspoonful  of  carbolic  acid  in 
a  bottle,  pour  on  it  half  a  pint  of  warm  water,  and  shake  the 
bottle  at  intervals  for  half  an  hour,  when  the  amount  of  oily 
residue  will  show  the  impurity.  Or,  dissolve  one  part  of  caustic 
soda  in  ten  parts  of  the  carbolic  acid.  As  before  the  residue 
will  indicate  the  amount  of  impurity. 
