Am  Jour.  Pharm^  ) 
Dec,  1885.  / 
Reviews. 
639 
A  Manual  of  Weights,  Measures  ayid  Specific  Gravity,  including  principles 
of  metrology  ;  the  weights  and  measures  now  in  use  ;  weight  and  volume, 
and  their  reciprocal  relations;  weighing  and  measuring;  balances 
(scales)  and  weights  ;  measures  of  capacity  ;  specific  weight  and  specific 
volume  and  their  determination  and  practical  npplicatioiis  ;  with  rules 
and  tables.  By  Oscar  Oldberg,  Pharm.D.,  Professor  of  Pharmacy  and 
director  of  the  pharmaceutical  laboratory  of  the  Chicago  College  of  Phar- 
macy.   Chicago  :  published  by  the  Author,  1885.    8vo,  pp.  238. 
The  confusion  which  has  heretofore  existed  in  medical  metrology  has 
toeen,  to  a  considerable  extent,  done  away  with  by  the  gradual  introduc- 
tion of  the  metric  system  in  most  civilized  countries.  It  cannot  be  denied 
that  this  system  in  English-speaking  countries  has  not  yet  gained  a  popu- 
lar foothold  to  such  a  degree  as  had  been  anticipated  by  its  more  sanguine 
iidvocates ;  but  it  should  also  be  remembered  that  in  France  where  the  sys- 
tem was  perfected  and  first  legally  introduced,  forty  or  fifty  years  were  neces- 
sary before  it  was  thoroughly  understood  and  used  by  the  general  public, 
while  at  the  present  time  scientists  throughout  the  whole  world  are  not 
•only  familiar  with  it,  but  employ  it  in  their  investigations.  We,  therefore, 
regai  d  its  general  use  merely  as  a  question  of  time.  This  would  probably 
be  favored,  if  existing  weights  were  so  far  modified  as  to  have  a  simple 
relation  to  the  metric  units  ;  at  any  rate  an  accurate  relation  is  as  desirable 
as  between  the  units  of  weight  and  measure  in  common  use. 
In  Great  Britain  the  imperial  fluidounce  in  use,  at  62°F.,  contains 
exactly  one  avoirdupois  ounce  =  437j  troygrains  of  water  ;  but  neither  the 
nmltiples  nor  the  subdivisions  agree  between  weight  and  measure,  or  have 
any  simple  relation  to  the  troygrains,  except  that  the  imperial  gallon  is 
equal  to  10  avoirdupois  pounds  or  70,000  troygrains.  The  wine  measure  in 
use  in  the  United  States  shows  no  su'^h  relation  to  either  avoirdupois  or  to 
troyweight  ;  but  the  subdivisions  of  the  fluidounce  adopted  for  medical 
and  pharmaceutical  use,  correspond  to  the  subdivisions  of  the  troyounce, 
though,  necessarily,  there  cannot  be  a  simple  equivalent  between  the  cor- 
responding weights  and  measures.  To  secure  such  a  simple  relation  the 
author  proposes  that  the  ounce  be  made  equal  to  32  grams  and  the  fluid- 
ounce  to  32  cubic  centimeters  ;  by  dividing  these  into  eight  parts,  the  drachm 
would  be  equal  to  4  grams  and  the  fluidrachm  to  4  cubic  centimeters.  Dis- 
carding the  scruples  the  units  would  then  be  the  gram  and  the  cubic  centi- 
meter or  fluigram,  and  by  dividing  these  into  sixteen  parts,  the  grain  and 
the  minim  would  be  obtained,  differing  but  very  slightly  from  the  same 
medicinal  weights  as  at  present  used.  Without  materially  altering  the 
present  values,  a  simple  relation  would  be  established  between  apotheca- 
ries' weights  and  measures  and  between  these  and  the  metric  system,  and 
at  the  same  time  the  larger  units  could  be  repeatedly  divided  by  two  with- 
out fractions  until  the  new  grain  and  new  minim  were  reached.  A 
fluidounce  of  water  at  its  greatest  density  would  then  weigh  exactly  one 
(new)  ounce  ;  but  if  it  was  made  to  weigh  that  at  a  medium  temj^erature 
of  20°  or  22°C.,  the  volume  would  be  about  \  per  cent,  greater  than  32  cubic 
centimeters. 
The  volume  deserves  to  be  carefully  read  and  considered  by  physicians 
and  pharmacists,  even  though  the  reader  may  not  agree  with  all  the  views 
advanced  by  the  author. 
