Am■JJuOne^;l903?^m•}  Commercial  Aloes.  267 
There  are  quite  a  number  of  reactions  that  are  characteristic  of 
Natal  aloes ;  but  as  this  variety  of  aloes  is  not  commercially  avail- 
able, it  will  not  be  necessary  to  do  more  than  mention  the  one 
usually  considered  to  be  the  most  reliable.  This  is  given  by  the 
United  States  Pharmacopoeia  practically  as  follows :  A  fragment  of 
the  suspected  aloes  is  mixed  with  sulphuric  acid ;  on  blowing  the 
fumes  of  nitric  acid  across  the  surface  of  the  mixture,  the  devel- 
opment of  a  blue  color  indicates  presence  of  Natal  aloes. 
ADULTERATIONS  AND  SOPHISTICATIONS. 
Aloes,  it  appears,  has  been  subject  to  adulterations  and  sophisti- 
cations from  the  very  earliest  time. 
Pliny,  in  his  "  Natural  History,"  book  27,  chapter  5,  says  :  "Aloes 
when  it  is  hard  and  black  should  be  rejected;  the  same,  too,  when  it 
is  mixed  with  gum  and  acacia,  a  fraud  which  may  be  easily  detected 
by  the  taste."  Pliny  also  refers  to  a  mineral  aloe  (probably  a  form 
of  bitumen);  this  he  considers  inferior  to  true  aloes.  It  will  be  seen 
from  this  reference  that  even  in  the  days  of  Pliny  aloes  was  not 
alone  adulterated,  but  a  foreign  substance  was  at  times  even  substi- 
tuted for  it. 
Socotrine  aloes,  even  down  to  our  own  time,  is  often  adulterated. 
This  subject,  the  adulteration  of  Socotrine  aloes,  was  one  to  which 
the  late  Dr.  Squibb  had  paid  particular  attention.  Much  of  our 
knowledge  on  the  subject  is  directly  due  to  his  work  and  observa- 
tions. Attention  had,  of  course,  been  repeatedly  called  to  the  gross 
adulteration  of  this  variety  of  aloes  by  other  writers.50  None  of 
them,  however,  ever  demonstrated  the  fact  as  clearly  as  Dr.  Squibb. 
At  the  present  time,  with  the  single  exception  of  some  of  the  aloes 
sold  as  Socotrine,  very  little  or  no  foreign  materials  are  found  in  the 
aloes  of  commerce. 
As  noted  in  the  introduction  to  this  essay,  there  appears  to  be  no 
hesitation,  however,  to  substitute  one  variety  of  aloes  for  another. 
This  substitution  appears  to  be  more  frequently  practiced  with  the 
powdered  drug.  This  fact  is  of  particular  importance  on  account  of 
the  widespread  preference  for  powdered  aloes ;  fully  90  per  cent,  of 
the  aloes  sold  to  retail  pharmacists  being  powdered. 
From  a  comparative  study  of  a  number  of  samples  obtained  from 
both  wholesale  and  retail  druggists  in  different  parts  of  the  United 
States  it  would  appear  that  much  of  the  aloes  sold  in  this  country  at 
the  present  time  is  not  true  to  name. 
