CONTRIBUTION  TO  STATISTICS  OF  DRUG  POWDERING.  115 
division  gives  the  invoice  neat  weights  and  the  results  thereon. 
It  is  well  known  that  commercial  usage  rarely  obtains  a  very 
accurate  weighing  of  drugs  in  the  market.  Gross  weights  are 
handed  down  through  jobbers  and  brokers,  often  without  verifica- 
tion, from  the  time  the  article  leaves  the  ship  or  manufactory 
until  it  is  received  at  the  mill  ;  during  which  time  it  may  have 
been  stored  in  damp  or  in  dry  places,  and  thus  have  changed  in 
weight.  Again  tares  are  rarely  accessible  in  the  markets,  but 
are  taken  from  original  markings  on  the  packages,  from  con- " 
version  of  foreign  weights,  or  percentage  allowance.  As  these 
usages  are  what  the  druggist  has  to  abide  by,  they  are  always 
obtained  as  carefully  as  possible,  and  the  losses  calculated  upon 
them,  since,  in  cases  where  the  weights  cannot  be  corrected,  or 
where  actual  weights  are  not  stipulated  for  in  purchasing,  these 
are  the  data  upon  which  the  druggist  must  make  up  his  cost 
price  of  the  powders. 
The  second  division  of  four  columns  shows  the  actual  neat 
weights,  of  the  drugs  at  the  time  of  receiving  them  at  the  mill, 
and  the  loss  calculated  upon  this  weight.  It  will  be  seen  that 
articles  which  contain  but  little  moisture,  and  therefore  lose  little 
by  drying,  as  gum  arabic,  catechu,  gamboge,  and  even  ipecac  and 
rhubarb,  show  small  losses  ;  and  these  losses  are  suffered  chiefly 
in  cleaning  the  mills  and  putting  up  the  powders  in  small  pack- 
ages, as  25  pound  boxes  ;  when  each  weighing  upon  any  ordinary 
scale,  takes  about  two  ounces  to  turn  the  scale.  If  such  losses, 
which  are  common  of  course  to  all  articles,  be  subtracted  from 
others  where  moisture  occurs,  the  remainder  will  show  the  excess 
of  moisture  for  such  articles. 
In  the  single  article  of  aloes,  every  package  is  melted,  thinned 
with  water  if  required,  and  strained  through  a  sieve  of  60  mashes 
to  the  linear  inch,  the  amount  of  sticks,  stones,  sand,  shreds  of 
aloe»plant,  pieces  of  goat  skin,  etc.,  thus  strained  out  varies 
very  much ;  in  rare  cases  amounting  to  31  per  cent.,  and  again 
falling  as  low  as  2  per  cent.,  and  often  averaging  as  much  as 
eight  per  cent.  This  of  course  very  much  increases  the  usual 
loss,  and  many  druggists  will  not  submit  to  it,  and  such  have 
always  been  desired  to  take  their  goods  to  other  mills. 
For  some  comparative  results,  a  table  of  losses  in  France  will 
