Am.  Tour.  Pharm.  1 
May,  1880.  J 
Gum-Hogg, 
(25B 
The  attention  of  the  writer  was  recently  called  to  this  article,  and  a? 
few  experiments  and  a  number  of  inquiries  made  with  a  view  to- 
determine  its  true  relation  to  Bassora  gum.  A  quantity  of  the  drug 
was  accordingly  obtained  from  the  same  house  which  furnished  the 
specimens  to  Dr.  Wood.  Upon  examination  it  does  not  present  quite 
the  same  physical  characteristics  which  are  described  by  him,  but 
appears  to  be  more  a  collection  of  gums  from  different  species  bearing; 
a  general  similarity  to  tragacanth.  It  occurs  in  fragments  of  irregular 
shape  and  varying  from  the  size  of  a  chestnut  to  much  larger  ;  its  color 
in  different  samples  varies  from  a  dirty  white  to  a  yellowish  brown  ;  it 
is  hard,  inodorous,  tasteless,  and  breaks  with  a  short  glassy  fracture. 
Some  fragments  have  still  adhering  portions  of  the  bark  of  the  tree 
from  which  it  has  been  obtained,  while  the  general  appearance  of  the 
gum  shows  it  to  have  been  deposited  in  successive  exudations,  similar 
to  tragacanth. 
A  portion  of  the  gum  was  set  aside  with  a  quantity  of  cold  water,, 
when,  after  the  expiration  of  twenty-four  hours  it  had  swollen  up  into> 
a  soft,  white,  transparent  mass,  occupying  the  lower  half  of  the  vessel. 
When  agitated,  this  mass  showed  no  disposition  to  form  a  uniform^ 
mucilage,  but  separated  into  small,  soft,  transparent,  and  rather  granu- 
lar fragments  resembling  pounded  ice  ;  this  subsided  to  the  bottom  of 
the  vessel  again  when  it  was  set  at  rest.  The  whole  was  now  thrown 
on  a  filter,  and  the  filtrate  examined;  it  gave  a  very  faint  precipitate 
with  sol.  subacetate  lead,  and  no  reaction  whatever  to  solution  oxalate 
ammonium  ;  it  was  neutral  in  reaction  and  had  neither  taste  nor  smelL. 
A  second  portion  of  the  gum  treated  by  prolonged  boiling  with  water 
gave  the  same  result  as  obtained  with  cold  water.  The  insoluble  por- 
tion was  next  examined.  Alcohol  and  ether  had  no  solvent  action  upon 
it  ;  boiled  with  dilute  sulphuric  acid  it  was  soon  dissolved,  the  resulting; 
solution  showing  no  reaction  with  tincture  of  iodine,  and  not  responding 
to  Trommer's  test  for  sugar.  When  boiled  with  a  weak  solution  of 
an  alkali  or  alkaline  carbonate  it  was  speedily  converted  into  a  uniform 
thick  mucilage  of  a  pinkish  color.  When  this  was  treated  with  an. 
acid  it  did  not  again  precipitate,  although  the  mucilage  lost  its  color  and 
became  perfectly  transparent.  The  loss  of  color  may  be  probably 
accounted  for  by  the  presence  of  iron  in  very  small  quantity.  These 
tests,  with  the  exception  of  perhaps  the  last,  on  which  there  is  little 
information,  correspond  with  those  for  bassorin,  and  show  the  close 
similarity  of  the  present  gum  with  that  previously  described  by  Dr.. 
