SULPHOCYANIDE  OF  MERCURY,  ETC. 
99 
Second.  That  the  resinous  matter  which  precipitates  when  the 
concentrated  tincture  of  the  root  is  poured  into  acidulated  water 
carries  down  with  it  a  notable  portion  of  the  alkaloid  insoluble 
in  ether. 
Third.  That  the  alkaloid  insoluble  in  ether,  when  administered 
in  small  doses,  has  a  very  perceptible  sedative  effect  on  the  cir- 
culation without  producing  any  other  disturbance. 
Fourth. — That  the  pure  resin  produces  sedative  effects  nearly 
or  quite  equal  to  those  obtained  from  the  alkaloid. 
February  19,  1866. 
SULPHOCYANIDE   OF    MERCURY— PHAROAH'S  SER- 
PENTS.   OLEATE  OP  SODA  AND  SOAP  BUBBLES. 
In  the  January  number  of  this  volume,  allusion  was  made  to  this 
salt,  and  its  use  as  a  toy.  An  esteemed  correspondent,  whose 
experience  in  the  manufacture  of  this  salt  has  rendered  him 
familiar  with  it,  has  sent  us  the  following  information,  which  he 
desires  to  be  anonymous.  Take  of  anhydrous  prussiate  of 
potash,  (ferrocyanide  of  potassium,)  in  fine  powder,  184  parts ; 
salt  of  tartar,  (carbonate  of  potassa,)  well  dried,  69  parts ;  sub- 
limed sulphur,  clean  and  dry,  128  parts ;  finely-powdered  char- 
coal, 6  parts ;  mix  them  thoroughly,  seeing  that  there  are  no 
lumps  of  aggregated  powder,  which  object  is  best  accomplished 
by  sifting;  and  a  little  extra  care  in  getting  the  materials 
thoroughly  pulverized  and  mixed  will  be  amply  repaid  by  the 
purity  of  the  product. 
Place  the  powder,  thus  prepared,  in  an  iron  vessel,  and  heat 
gently,  (not  quite  to  redness,)  when  the  edges  and  bottom  of  the 
mass  become  fused  to  about  the  depth  of  half  an  inch,  stir  it 
thoroughly  and  rapidly  with  an  iron  rod,  so  as  to  melt  the  whole 
down  as  soon  as  possible.  When  it  ceases  to  flame,  and  reaches 
a  state  of  nearly  tranquil  fusion,  which  is  attained  at  a  heat 
materially  below  redness,  it  is  to  be  cooled;  then  dissolved 
in  about  six  or  eight  times  its  weight  of  water,  and  filtered  or 
strained  to  separate  the  insoluble  sulphuret  of  iron.  The  clear 
solution  may  be  considered  to  be  a  tolerably  pure  solution  of 
