ANovJembef,hi!99m-}       Valuation  of  Drugs  and  Foods.  541 
The  method  of  Hager  is  a  simple  one  and  deserving  of  attention 
from  a  practical  standpoint,  as  chemical  assays  of  a  lot  of  jalap 
tubers  represent  the  values  of  but  a  few  tubers,  unless  the  whole  lot 
is  in  a  ground  or  powdered  condition. 
(C)  The  author  has  been  desirous  of  applying  this  method  of 
examination  to  rhubarb  and  inula,  taraxacum  and  a  number  of  other 
inulin-containing  drugs,  but  want  of  time  has  prevented  this  work 
being  done. 
(D)  Absorbent  Cotton. — "  In  addition  to  the  ordinary  test  applied 
to  determine  the  value  of  absorbent  cotton,  it  has  been  proposed 
{Schweiz.  Woch.  Pharm.,  1899,  20)  to  test  its  elasticity  by  observ- 
ing the  weight  required  to  compress  a  given  weight  of  cotton  into 
a  definite  space.  A  comparison  has  proven  that  the  lower  grades 
of  absorbent  cotton  made  from  the  sweepings,  etc.,  have  much  less 
resiliency  than  has  that  of  good  quality  made  from  the  high-grade 
American  cotton." 
Equally  important,  however,  is  the  measure  of  the  length  of  fibres 
and  the  determination  of  the  amount  of  oil  adhering  to  them.  For 
the  latter  test  the  cotton  fibres  are  mounted  in  a  saturated  chloral 
solution,  when  the  oil  globules  adhering  to  the  fibres  are  manifested 
in  the  mount. 
(£)  The  gelatinization  test  given  by  the  U.S.P.  under  chondrus 
is  worthy  also  of  an  extended  application  to  all  drugs  containing 
gums  or  mucilages.  The  writer  finds  that  the  purity  of  powdered 
acacia  may  be  readily  ascertained  on  mixing  0  500  gramme  of  the 
powder  with  about  17  minims  of  water  at  about  300  C,  when,  if 
the  acacia  is  pure,  there  will  be  produced  shortly  a  clear  mucilagi- 
nous mass.  With  dextrins,  or  a  gum  arabic  containing  dextrin,  the 
resulting  mass  is  either  cloudy  or  less  cohesive,  or  both. 
III.  MICROSCOPICAL  METHODS. 
The  microscope  may  ofttimes  be  utilized  when  other  methods 
of  valuation  fail.  The  microscope  is  an  important  adjunct  in 
determining  the  percentage  value  of  certain  foods  and  drugs, 
as  in  the  cereals,  spices,  etc.,  when  starchy  materials  are  used  to 
adulterate  them.  It  does  not  appear  necessary  to  dwell  upon  this 
work  here,  the  author  deeming  it  sufficient  to  refer  to  his  previous 
communications  on  this  subject  as  published  in  the  "  Proceedings  of 
the  A.  Ph.  A./'  and  in  the  American  Journal  of  Pharmacy,  and 
