Arn'oc^'imarm*}    British  Pharmaceutical  Conference.  521 
only  slightly  in  chemical  composition  and  therapeutic  action  from  strophan- 
thin  is  now  manufactured  from  a  smooth  variety  of  strophanthus  seeds,  instead 
of  the  wood  from  which  it  was  first  prepared.  At  the  conclusion  of  the  reading 
of  this  paper  a  short  note  by  Mr.  T.  Christy  was  read,  accompanying  two  leaves 
of  a  plant  grown  at  Sydenham  from  seed  similar  to  that  from  which  M. 
Arnaud  has  separated  ouabain.  In  the  discussion  that  followed,  Mr.  Martin 
bore  testimony  that  the  results  upon  which  the  reputation  of  the  drug  was 
founded  were  obtained  with  preparations  of  greenish-fawn  seeds  and  that  other 
kinds  have  not  produced  such  satisfactory  effects. 
Nitrites  in  Potable  Waters,  by  Dr.  J.  C.  Thresh. — The  author  remarked  that 
although  a  quantitative  estimation  of  the  nitrites  did  not  seem  to  be  of  much 
assistance  in  determining  the  quality  of  a  water  in  the  present  state  of  knowl- 
edge, probably  no  analyst  felt  he  had  made  a  complete  examination  of  a  water 
unless  he  had  made  at  least  a  qualitative  test  for  them,  and  if  he  found  indica- 
tions of  them  he  justly  regarded  the  water  with  suspicion.  But  a  series  of 
experiments  Dr.  Thresh  has  been  making  on  the  changes  in  composition  of 
certain  waters  kept  under  varied  conditions  have  led  him  to  believe  that 
before  long  the  study  of  these  changes  would  be  of  great  aid  in  forming  a 
judgment  of  the  quality  of  a  water,  and  especially  of  such  as  the  analyst  now 
only  reports  to  be  suspicious.  One  of  these  changes  is  the  variation  in  the 
amount  of  nitrous  nitrogen.  In  working  out  the  subject  the  want  of  a  simple 
and  reliable  quantitative  test  for  nitrites  has  been  much  felt  and  eventually 
Dr.  Thresh  succeeded  in  making  the  old  potassium  iodide  and  starch  test  for 
nitrites  a  reliable  colorimetric  quantitative  one  for  water  analysis.  The  pre- 
paration of  the  reagents  and  the  method  of  working  were  then  described  and 
Dr.  Thresh  concluded  by  giving  a  practical  demonstration  of  the  great  delicacy 
of  the  test.  In  reference  to  Dr.  Thresh's  remark  as  to  the  changes  that  take 
place  sometimes  in  a  water,  Mr.  F.  M.  Rimmington  said  that  the  character  of 
the  Bradford  water  had  undergone  a  great  change  since  the  last  dry  summer. 
Mr.  Siebold  also  thought  the  time  would  come  when  it  would  be  the  practice 
to  watch  a  water  for  some  time  before  pronouncing  upon  its  quality,  and  stated 
that  on  one  occasion  he  obtained  indications  of  the  probable  presence  of  a 
ptomaine  in  a  water. 
The  Conference  then  adjourned  for  luncheon.  Upon  resuming,  Mr.  Naylor, 
in  the  absence  of  the  authors,  gave  a  resume  of  the  next  two  papers. 
Chloroform  as  a  Preservative,  by  J.  F.  Burnett  and  H.  Wyatt. — Mr.  Burnett 
gave  a  list  of  solutions  made  with  chloroform  water  which  he  keeps  for  dis- 
pensing purposes,  and  testified  to  the  value  of  chloroform  in  preserving  infu- 
sions. Two  other  instances  mentioned  were  mixtures  of  powdered  rhubarb 
and  aromatic  powder  of  chalk,  which  he  keeps  rubbed  down  with  chloroform 
water  (1  in  8).  Mr.  Wyatt,  among  other  instances,  recorded  the  preservative 
action  of  chloroform  when  added,  to  an  extract  of  ergot  mixture  containing 
strychnine,  as  well  as  to  essence  of  rennet  and  cucumber  juice.  The  discus- 
sion that  followed  the  reading  of  the  papers  showed  a  general  concensus  of 
opinion  among  those  present  as  to  the  value  of  chloroform  as  a  preservative 
agent,  and  the  opinion  was  expressed  that  under  medical  authority  it  might 
often  be  advantageously  used  and  sometimes  take  the  place  of  alcohol. 
Arsenic  in  Glycerin. — In  a  short  note  Mr.  Siebold  referred  to  the  opinion 
