Am.  Jour.  Pharm. 
June,  1903. 
Commercial  Aloes. 
271 
markets,  and  none  of  the  available  price-lists  of  foreign  drug  houses 
give  any  description  of  the  size  of  the  package. 
CONCLUSIONS. 
From  what  has  been  said  it  would  appear  that  the  different  varie- 
ties of  aloes  on  the  market  at  the  present  time  may  be  divided  into 
two  classes  or  groups :  one  containing  barb-aloin  with  little  or  no 
iso-barb-aloin,  and  the  other  containing  considerable  quantities  of 
iso-barb-aloin  in  addition  to  the  barb-aloin. 
Sufficient  aloes  of  good  quality  is  available  at  the  present  time  to 
warrant  the  introduction  of  restrictions  as  to  purity  and  water  con- 
tent, that  would  do  away  with  retaining  in  our  Pharmacopoeia  the 
title  and  formula  for  "  Aloe  Purificata." 
With  continued  research  into  the  chemistry  of  aloes  it  is  also 
quite  probable  that  the  immediate  future  will  give  us  a  modified 
aloin,  or  an  analogous  compound  that  will  more  nearly  represent 
the  active  cathartic  principle  of  aloes  than  does  the  aloin  available 
at  the  present  time. 
The  general  use  of  powdered  aloes  would  facilitate  testing  for  im- 
purities and  guarantee  a  product  fairly  even  as  to  water  content. 
As  an  outline  for  a  pharmacopceial  heading  for  aloes  the  follow- 
ing may  be  suggested : 
ALOE- ALOES. 
The  inspissated  juice  of  different  species  of  aloe  grown  in  tropical 
or  sub-tropical  climates. 
Aloes  varies  from  reddish  brown  to  deep  black  in  color  and  may 
have  a  glossy  or  opaque  surface,  according  to  the  mode  of  prepara- 
tion. 
Powdered  aloes  may  vary  from  light  yellow  to  brown  or  greenish 
brown  in  color.  Aloes  should  not  contain  more  than  10  per  cent, 
of  water,  and  leave  on  incineration  not  more  than  3-5  per  cent,  of 
ash.  It  should  be  almost  entirely  soluble  in  50  per  cent,  alcohol, 
U.S.P.  acetic  acid  or  a  I  per  cent,  solution  of  ammonium  hydrate. 
Aloes  should  react  to  Borntraeger's  test  for  emodin.  On  mixing 
a  small  quantity  of  aloes  with  strong  sulphuric  acid  and  blowing  the 
fumes  of  nitric  acid  over  the  surface  of  the  mixture,  it  should  not 
assume  a  blue  color — absence  of  Natal  aloes. 
Aloes  may  be  divided  into  two  general  groups  or  classes : 
