228 
Indexing  of  Periodicals. 
Am.  Jour.  Pharnx 
May,  1877. 
the  unit  of  weight,  the  gram — the  weight  of  a  cubic  centimeter  of 
water. 
These  four  units  are  subdivided  into  tenth,  hundredth  and  thou- 
sandth parts,  which  are  denominated  by  the  syllables  derived  from  the 
Latin,  deci,  centi  and  milli  ;  the  muliples  are  similarly  by  tens,  hun- 
dreds, thousands  and  ten  thousands,  distinguished  by  the  prefixes  bor- 
rowed from  the  Greek,  of  deca,  hecta,  kilo  and  myria. 
The  whole  of  the  multiples  and  subdivisions  of  the  metric  system 
are  decimal,  and  the  reduction  from  one  denomination  to  the  other  is 
performed  by  multiplying  by  ten  or  its  multiples,  or  dividing  by  them. 
There  is  no  necessity  to  alter  the  figures,  but  merely  to  read  them  dif- 
ferently, by  placing  the  decimal  point  so  many  places,  according  to  the 
terms  of  the  required  denomination. 
No  system  of  metrology  hitherto  invented  can  be  compared  with 
this  of  the  French  in  a  scientific  point  of  view,  while  its  convenience 
for  the  purposes  of  commerce  or  pharmacy  is  now  so  generally  admit- 
ted by  those  who  have  made  themselves  intimately  acquainted  with  its 
workings,  that  the  universal  adoption  to  pharmacv  cannot  be  much 
longer  delayed. 
INDEXING  OF  PERIODICALS. 
By  Hans  M.  Wilder. 
Mr.  Moore's  article  on  the  external  treatment  of  books  suggests  to 
me  that  a  few  words  concerning  their  internal  treatment  might  not  be 
amiss. 
When,  in  the  course  of  our  readings,  we  come  across  a  statement 
which  may  be  of  use  to  us,  or,  for  one  reason  or  other,  interests  us, 
we  "  make  a  note  of  it"  (so  to  speak)  in  our  mind.  This  will  do  for 
awhile,  particularly  respecting  books,  etc.,  in  our  possession,  which  we 
can  consult  at  any  time.  We  soon  find  out,  however,  that  our  mem- 
ory is  quite  unreliable,  particularly  in  regard  to  figures  ;  for  this  reason, 
and  because  we  read  many  books  and  periodicals  which  we  seldom  or 
never  have  occasion  to  consult  again,  we  keep  a  memorandum  book  in 
which  we  jot  down  the  chief  points,  figures,  etc.,  not  forgetting  refer- 
ence to  book,  volume  and  page.  Provided  we  keep  pace  with  the  pro- 
gress of  our  profession,  it  will  not  take  a  long  time  before  said  memo- 
randum book  swells  to,  it  may  be,  a  hundred  pages  or  more,  and  we 
find  it  necessary  to  make  an  alphabetical  register  to  facilitate  the  find- 
