ASidmieT.mS1'}    Recent  Literature  Relating  to  Pharmacy.  6o$ 
RECENT  LITERATURE  RELATING  TO  PHARMACY. 
THE   RECORDED  HISTORY  OF  THE  MEMBERS   OF  THE  ARGON  GROUP. 
This  is  the  title  of  a  paper  by  Henry  P.  Talbot,  published  in  the 
M  Technology  Quarterly,"  for  June,  1902,  page  195.  In  this  paper 
the  writer  presents  a  review  of  physical  and  chemical,  as  well  as 
historical  data. 
The  amount  of  interest  that  these  new  elements  have  excited  is 
well  illustrated  by  the  closing  paragraph  of  the  paper,  in  which  the 
writer  states,  that  since  the  discovery  of  Argon,  no  less  than  250 
magazine  articles  have  appeared  relating  to  one  or  more  members 
of  this  group.  The  following  facts  and  figures  have  been  culled 
from  this  interesting  and  comprehensive  review : 
Argon. — The  circumstances  that  lead  up  to  the  discovery  of  this 
element  may  be  found  in  the  fact  that  Lord  Rayleigh,  in  the  course 
of  some  experiments,  had  noted  that  atmospheric  nitrogen  appeared 
to  have  a  greater  density  than  nitrogen  obtained  from  chemicals, 
such  as  nitric  acid,  nitrous  oxide  or  ammonium  nitrite.  Suggestions 
and  explanations  were  numerous  but  unsatisfactory,  and  it  was 
finally  decided  to  determine  whether  or  not  there  was  an  unknown 
heavier  element  in  the  atmospheric  nitrogen. 
In  making  these  investigations  Lord  Rayleigh  had  associated  with 
him  Professor  Ramsay,  of  University  College,  London.  After  a  long 
series  of  carefully  planned  and  executed  experiments,  Lord  Rayleigh 
and  Professor  Ramsay,  on  January  31,  1895,  made  the  announce- 
ment, at  a  meeting  of  the  Royal  Society  in  London,  that  they  had 
discovered  a  new  element  in  the  atmosphere,  to  which,  on  account 
of  its  inert  character,  they  had  given  the  name  Argon.  The  quan- 
tity of  this  element,  present  in  the  atmosphere,  appeared  to  be 
about  I  per  cent,  of  the  contained  nitrogen,  or  about  0-9  per  cent, 
of  the  atmosphere.  Assuming  that  the  density  of  Argon  was  about 
20,  it  would  explain  the  greater  density  of  atmospheric  compared 
with  chemical  nitrogen.  Argon  has  since  then  been  found  in  one 
specimen  of  meteoric  iron,  in  a  variety  of  minerals  and  in  the  waters, 
or  escaping  gases,  from  a  number  of  springs  in  different  parts  of 
Europe. 
So  far  it  has  not  been  definitely  demonstrated  to  have  any  chemi- 
cal properties.  Its  physical  properties,  that  is,  its  spectrum,  its  spe- 
cific gravity  and  the  atomicity  of  its  molecule  have  been  the  subject 
