158  Minutes  of  the  Pharmaceutical  Meeting.  {AmMa0rch,i&9rm' 
negative.  A  suitable  varnish  may  be  made  from  seed-lac  and  methylated 
spirit,  about  3  ounces  of  the  former  to  a  pint  of  the  latter.  Before  using, 
the  back  of  the  negative  is  gently  warmed  over  a  spirit  lamp*  or  before  the 
fire,  and  a  pool  of  varnish  poured  on  the  film,  allowed  to  run  over  the  entire 
surface,  and  then  drained  off  at  the  opposite  corner. 
The  alkaline  "  pyro  "  developer  always  stains  the  film  more  or  less,  thus 
retarding  the  subsequent  process  of  printing ;  it  is  usual,  therefore,  to  put 
the  plate  directly  after  development  and  just  before  fixing  into  what  is 
called  the  "  clearing  "  solution.  This  consists  of  a  solution  of  citric  acid  and 
alum,  about  an  ounce  of  each  to  a  pint  of  water,  care  being  taken  afterwards 
to  rinse  the  plate  well  in  clean  water  before  immersing  it  in  the  bath  of 
"hypo,"  as  the  acid  it  contains  is  liable  to  decompose  the  sodium  thiosul- 
phate,  liberating  hyposulphurous  acid,  which  at  once  splits  up  into  sulphu- 
rous acid  and  free  sulphur,  which  is  deposited  in  the  film. 
2H2S203=2H2S03+S2. 
The  solution  of  "  hypo  "  used  for  "  fixing  "  plates  or  prints  may  be  used 
over  and  over  again  for  subsequent  batches,  but  it  must  not  on  any  account, 
through  too  frequent  use,  be  allowed  to  get  too  iveak,  because  sodium  thi- 
osulphate  forms  two  double  salts  with  silver  chloride,  one  being  soluble,  the 
other  msoluble,  and  with  a  weak  solution  there  is  great  danger  of  the  latter 
being  formed :— AgCl+Na2S203=AgNaS203+:N"aCl. 
(To  be  concluded). 
MINUTES  OF  THE  PHAEMACEUTICAL  MEETING. 
Philadelphia,  February  19th,  1889. 
On  motion  of  Dr.  C.  B.  Lowe,  Wm.  B.  Webb,  Ph.  M.,  was  called  to  pre- 
side. The  minutes  of  the  last  meeting  were  read  and  no  alterations  being 
required  they  stand  approved. 
The  Eegistrar  reported  that  there  had  been  presented  to  the  library  the 
following  works  :  Proceedings  of  the  American  Pharmaceutical  Association 
for  1888 ;  Notes  of  Professor  Curtman's  Lectures  reported  by  Professor  H. 
M.  Whelpley,  two  volumes  ;  Pharmacopoeia  of  the  London  Throat  Hospital ; 
Report  of  the  Pennsylvania  State  Board  of  Health,  1886  and  1887  ;  Report  of 
the  Illinois  Board  of  Pharmacy,  1887,  and  Report  of  the  Commissioner  of 
Education  for  1886-87.  Appropriate  acknowledgements  of  the  same  have 
already  been  made. 
The  Registrar  read  a  paper  by  J.  W.  England,  Ph.  G.,  who  was  unable  to 
be  present,  upon  tincture  of  mustard.  A  discussion  ensued  upon  the  subject 
and  it  was  suggested  that  it  would  be  well  to  state  that  the  maceration,  after 
moistening  the  drug  with  water  and  after  transferring  it  to  the  percolator, 
should  be  effected  in  closed  vessels  to  prevent  loss  of  the  volatile  oil. 
A  paper  upon  hydrangin  by  H.  J.  M.  Schroeter,  Ph.  G.,  was  read  and 
listened  to  with  much  attention.  Some  conversation  ensued  and  Wm. 
Webb  remarked  that  when  the  fluid  extract  was  introduced  it  was  recom- 
