416 
A  Standard  Dosage  Measure.      { Am\j£ 
To  overcome  the  unreliability  of  the  spoons,  the  glass  manu- 
facturers have  placed  upon  the  market  medicine  glasses  and  medi- 
cine goblets,  of  various  shapes  and  sizes,  marked  for  the  measure- 
ment of  teaspoonfuls,  dessertspoonfuls,  tablespoonfuls,  etc.  Un- 
fortunately, the  shapes  selected  have  not  been  such  as  would  permit 
of  accurate  measurement  and  in  some  cases  the  graduation  has  been 
very  careless  and  inaccurate  and  the  common  medicine  glass  shows 
very  little  if  any  advantage  in  accuracy  over  the  variable  spoon.  It 
is  apparent  that  60  minims  of  a  liquid  distributed  over  the  bottom 
of  a  broad  tumbler  or  goblet  shaped  vessel,  will  make  so  little  show- 
ing that  it  will  be  difficult  to  gauge  and  to  properly  graduate  this, 
and  it  will  be  impracticable  to  indicate  lesser  amounts. 
The  commonly  employed  medicine  dropper  for  measuring  medi- 
cines directed  to  be  given  in  doses  of  so  many  minims  or  drops  is 
likewise  far  from  accurate.  This  can  be  readily  demonstrated  by 
measuring  accurately  the  same  number  of  drops  of  the  same  liquid 
as  dropped  by  a  number  of  these. 
The  physician  has  in  mind  a  definite  amount  of  liquid  as  the 
equivalent  of  the  dosage  term  he  uses.  It  is  almost  an  invariable 
rule,  that  to  him  a  drop  is  one  minim,  a  teaspoonf ul  is  one  flui- 
drachm,  a  dessertspoonful  is  two  fluidrachms,  a  tablespoonful  is 
four  fluidrachms  or  a  half  fluidounce.  Upon  these  equivalents  he 
bases  his  calculations  for  the  intended  doses  of  the  medicaments  in 
his  prescriptions.  Practically  all  of  the  formulas  in  use  by  physicians 
and  published  in  the  works  on  medicine  and  the  treatment  of  dis- 
eases, are  based  upon  these  commonly  accepted  equivalents,  and  these 
have  also  been  generally  employed  in  the  "  ready-made  medicines  " 
so  frequently  dispensed. 
The  United  States  Pharmacopoeia  IX  recognized  the  seriousness 
of  the  prevailing  inaccuracy  in  the  administration  of  liquid  medi- 
cines and  while  not  adopting  the  suggestion  that  a  standard  form  for 
a  dosage  measure  should  be  defined,  the  Committee  of  Revision 
compromised  by  making  in  the  "  Introductory  Notices  "  the  follow- 
ing statement  on  page  li. 
"  Physicians  have  hitherto  ver)^  commonly  prescribed  liquid 
medicines  in  teaspoonful,  dessertspoonful  or  tablespoonful  doses. 
Inasmuch  as  spoons  vary  greatly  in  capacity,  and  from  their  form 
are  unfit  for  use  in  the  dosage  of  medicines,  it  is  desirable  that  the 
Approximate  Measures. 
/ 
