524  British  Pharmaceutical  Conference.  {Am-oct!!'i89o.arm" 
ing  and  formation  of  red  iodide.  The  trituration  should  be  continued  until 
all  metallic  globules  have  disappeared,  and  the  mass  assumes  a  uniform  green 
color,  when  it  should  be  dried  by  exposure  to  the  air  on  filter  paper  in  a  dark 
room  and  preserved  in  an  opaque  bottle.  The  product  will  contain  about  12 '6 
per  cent,  of  free  mercury,  a  quantity  that  has  been  found  by  a  specialist  to  be 
no  detriment,  and  which  was  exceeded  in  a  commercial  sample  examined. 
The  authors  state  that  pills  of  green  iodide  of  mercury  are  best  massed  with 
sugar  of  milk,  syrup  and  gum,  and  their  sap-green  color  may  be  taken  as  evi- 
dence of  quality.  The  pills  may  be  coated  with  sandarach  solution,  and  should 
be  sent  out  in  amber-colored  bottles.  The  paper  evoked  considerable  discus- 
sion, and  there  was  a  decided  divergence  of  opinion  as  to  whether  the  insta- 
bility of  a  preparation  justified  its  exclusion  from  the  Pharmacopoeia  or  really 
made  it  more  desirable  that  there  should  be  an  official  standard  and  an  author- 
ized method  of  preparation. 
Cream  of  Tartar. — Mr.  H.  Broadbent  gave  the  average  results  of  the  exami- 
nation of  a  large  number  of  samples  of  cream  of  tartar,  of  French,  Italian, 
Spanish  and  German  origin,  from  which  it  appeared  that  the  article  comes 
into  this  country  from  all  these  sources  of  tolerably  uniform  quality,  answer- 
ing fairly  well  to  the  requirements  of  the  British  Pharmacopoeia. 
At  this  moment,  Sir  Frederick  Abel,  the  President  of  the  British  Association, 
entered  the  theatre,  together  with  Professor  Thorpe. 
The  next  communication  partook  of  the  nature  of  a  blackboard  demonstra- 
tion by  Mr.  John  Hodgkin,  having  for  its  object  to  explain  from  a  chemical 
point  of  view  the  constitution  of  the  principal  new  synthetic  remedies,  and  to 
show  their  relationship  one  to  another.  Commencing  with  the  fatty  group, 
the  methane  derivatives  were  first  illustrated  by  graphic  formulae,  including 
methyl  chloride,  methylene  chloride,  chloroform,  methylal,  amylene  hydrate, 
sulphonal,  trional  and  tetronal.  Next  came  the  compounds  of  the  formic  acid 
type,  such  as  hypnone,  urethane,  paraldehyd,  chloral,  ural,  somnal,  chloral- 
amide  and  butyl-chloral.  The  aromatic  series  of  synthetic  remedies  was  also 
for  convenience  divided  into  two  groups,  the  benzene  group,  including  the 
aniline,  benzoic  acid  and  phenol  derivatives,  and  the  naphthalene  group, 
including  the  naphthylamine,  naphthoic  acid,  naphthol  and  quinoline  deriva- 
tives. Of  the  first  group  there  were  illustrated  acetanilide,  benzanilide,  exal- 
gine,  pyrodin,  antithermin,  antipyrin,  antisepsin,  phenacetin,  methacetin, 
methylphenacetin,  benzoic  acid,  salicylic  acid,  salol,  dithiosalicylic  acid,  phenol 
trichlorphenol,  aseptol,  sozoiodol,  cresalol  and  aristol.  The  second  group 
included  thermine,  a-  and  ^3-naphthol,  betol,  quinoline,  kairolin,  kairin,  thal- 
lin,  orexin  and  iodol. 
At  the  close  of  the  paper,  Sir  Frederick  Abel  expressed  the  pleasure  it  had 
given  him  to  be  able  to  visit  the  Conference  during  its  sitting,  and  assured  the 
members  of  his  sympathy  in  their  efforts  to  advance  the  chemical  side  of 
pharmacy. 
Estimation  of  Mineral  Oil. — It  is  frequently  found  that  the  "recovered 
oils  "  supplied  for  use  in  the  woollen  and  leather  industries  contain  large 
quantities  of  mineral  oil  or  unsaponifiable  or  resinous  matter,  which  is 
difficult  to  estimate.  A  method  for  effecting  this  was  described  by  Messrs. 
Fairley  and  Burrell. 
