424 
Atmospheric  Ozone. 
(Am.  Jour.  Pharm 
\  September,  1900. 
ozone  assay ;  ozone  oxidizing  arsenite  to  arsenate,  and  the  ozone 
factor  is  deduced  by  calculation  of  loss  of  arsenite. 
The  detection  and  quantitative  estimation  of  ozone  in  the  atmos- 
phere are  particularly  difficult,  because  of  its  minute  proportion 
and  by  reason  of  the  numerous  normal  and  abnormal  constituents 
of  the  atmosphere,  which  interfere  with  the  test.  It  is,  therefore, 
not  surprising  that  widely  varying  and  even  contradictory  results 
are  obtained  by  equally  competent  observers ;  not  only  as  to  con- 
ditions, time  of  day  and  season  when  greatest  amount  is  present, 
but  also  as  to  meteorological  changes  and  maximum  amount.  Its 
very  source  is  still  a  problem,  being  variously  attributed  to  action 
of  sunlight,  to  evaporation  of  moisture  (fresh  and  saline  solutions), 
to  electrical  discharges  (abundantly  proven),  to  plant-life  processes ; 
indeed,  one  authority  suggests  the  moist  mucous  membrane  of  the 
respiratory  tract  is  capable  of  converting  all  the  oxygen  entering 
the  blood  into  ozone  ! 
The  work  done  by  the  Michigan  Board  of  Health  to  determine 
the  presence  of  atmospheric  ozone  and  its  relation  to  disease  or 
health  has  been  very  extensive  and  along  lines  which  should  lead 
to  valuable  results.  Nicholson  (Rep.  Mich.  Bd.,  1880)  has  made 
numerous  ingenious  and  interesting  observations  under  conditions 
of  hygienic  interest.  It  is,  however,  much  to  be  regretted  that  the 
unreliable  Schbnbein  paper  was  used  in  all  his  work,  thereby 
vitiating  much  of  his  data.  For  instance,  he  draws  conclusions 
from  the  coloration  of  the  paper  when  placed  near  charcoal  pits 
and  over  swamps,  despite  the  fact  that  Bastaudin  has  shown  that 
iodine  is  liberated  from  potassium  iodide  by  carbonic  acid,  while 
Papasogli  reports  that  similar  decomposition  is  accomplished  by 
carbon  dioxide  (Nat'l  Disp.,  p.  1302).  These  reactions  easily 
explain  the  coloration  of  Schonbein's  paper  cited  above. 
In  the  same  manner,  Dr.  Prestel  (Brochure,  Dresden,  1865)  took 
daily  observations  at  Emden,  from  1857  to  1864,  with  special  refer- 
ence to  influence  of  winds  and  of  time  (day,  night  or  season). 
Dr.  Ambrook  (Rep.  Col.  Bd.  Health,  1877)  made  similar  observa- 
tions, but  with  totally  different  results.  To  quote  his  words,  "  a 
careful  research  of  the  literature  at  my  command  has  impressed  me 
with  the  belief  that  the  'Ghost  that  Schbnbein  raised'  will  not  be 
so  easily  laid,  for  a  more  contradictory  set  of  results,  from  appar- 
ently equally  competent  observers,  is  hard  to  find  than  is  the  record 
about  ozone." 
