Ar.i   Jour.  Pharm.  j 
April,  1918.  > 
Current  Literature. 
299 
of  the  salt  is  dissolved  in  50  Cc.  of  cold  water,  and  the  liquid,  after 
treatment  with  1  Grm.  of  sodium  chloride  and  a  drop  of  0.2  per 
cent,  methyl-orange  solution,  is  titrated  with  N/10  hydrochloric 
acid  until  it  turns  red.  After  the  volume  of  acid  required  is  read, 
2  Grms.  of  potassium  iodide  are  added  to  the  solution,  and  the  yel- 
low liquid  thus  obtained  is  again  titrated  with  N/10  hydrochloric 
acid  as  before.  From  the  two  volumes  of  acid  required  the  per- 
centages of  oxycyanide  and  cyanide  in  the  salt  may  be  calcu- 
lated, the  reactions  proceeding  according  to  the  equations :  ( 1 ) 
HgO,  Hg(CN)2  +  2HCl  =  HgCl2  +  Hg(CN)2  +  H20,  and  (2) 
Hg(CN)2  +  4KI  +  2HCI  =  HgK2I4  +  2KCI  +  2HCN. — A.  Taglia- 
vini.  Boll,  Chim.  Farm.,  1917,  56,  297-299;  through  /.  Chem.  Soc., 
19 1 7,  112,  II,  510.)  From  Food  and  Drug  Analysis  through  The 
Analyst. 
Estimation  of  Mercury  in  Galenical  Preparations. — The 
method  of  destroying  organic  matter  previously  employed  in  an- 
alyzing protein  preparations  containing  silver  is  applied  to  the  de- 
termination of  mercury  in  galenical  preparations.  The  substance 
(0.3  to 0.5  Grm.)  is  heated  with  concentrated  sulphuric  acid  (10  Cc.) 
and  nitric  acid  (sp.  gr.  1.4,  3  Cc.)  until  reddish-yellow  vapors  are 
not  further  evolved,  the  liquid  becomes  clear  and  colorless,  and  the 
flask  is  filled  with  sulphuric  acid  fumes.  If  the  vapors  still  smell  of 
sulphur  dioxide,  treatment  with  nitric  acid  (3  Cc.)  is  repeated. 
After  being  cooled,  water  (25  Cc.)  is  added,  which  is  removed  by 
evaporation.  The  cold  solution  is  treated  with  water  (15  Cc.)  and 
potassium  permanganate  solution  until  a  permanent  pink  coloration 
is  produced ;  the  latter  is  discharged  with  ferrous  sulphate,  the  solu- 
tion diluted  with  water  (75  Cc.)  and  titrated  with  N/10  ammonium 
thiocyanate  solution  in  the  presence  of  ferric  alum.  The  method  is 
suitable  for  organic  and  inorganic  preparations  of  the  oxides  of 
mercury,  but  not  for  such  as  contain  the  haloids.  It  can  also  be 
used  for  estimating  mercury  in  plasters  and  pills,  and  in  ointments, 
provided  that  they  are  tolerably  free  from  paraffin. — H.  Wastenson. 
(Pharm.  Post.,  1917,  50,  125-126;  through  /.  Chem.  Soc.,  1917,  112, 
II,  509.)    From  Food  and  Drug  Analysis,  through  The  Analyst. 
Volumetric  Estimation  of  Zinc  Phenolsulphonate. — In  the 
presence  of  bromine  and  an  acid,  zinc  phenolsulphonate  reacts  in 
accordance  with  the  following  equations:   (OH -CeH^SC^Zn, 
