GLEANINGS  FROM  FOREIGN  JOURNALS. 
313 
with  metallic  lead.  Four  ounces  nitrate  potassa  with  an  equal 
weight  of  lead  are  melted  together  in  an  iron  pan  to  a  dull  red 
heat,  with  constant  stirring  and  the  addition  of  about  an 
ounce  of  lead.  After  the  lead  is  mostly  oxidized,  it  is  heated 
to  strong  redness.  The  undecomposed  nitrate  is  separated  by 
crystallization,  and  the  oxide  of  lead  remains  as  a  very  fine 
powder.  To  prepare  the  nitrous  ether,  the  solution  of  the  ni- 
trite is  allowed  to  flow  steadily  into  a  mixture  of  alcohol  and 
sulphuric  acid  ;  or,  on  the  other  hand,  the  acid  mixture  may  be 
added  gradually  to  the  nitrite  in  pieces  the  size  of  a  nut.  The 
nitrous  ether  begins  to  form  immediately,  without  the  applica- 
tion of  heat.  From  500  grms.  fused  nitrite  of  potassa,  and 
500  grms.  sulphuric  acid,  alcohol  and  water,  255  grms.  nitrous 
ether  may  be  obtained.  Thus  prepared  it  is  somewhat  acid, 
which  may  be  neutralized  in  the  usual  way.  The  author  con- 
siders this  process  an  economical  one  for  the  production  of 
sweet  spirits  of  nitre,  which  contains  from  1  to  5  per  cent,  of 
this  ether. — Ann.  Oh.  u  Pharm.  cxxvi.  71,  i^.  Jahrb.  Ph. 
xx.  93. 
Permanganate  of  Potassa  is  recommended  as  a  rapid  and 
excellent*  stain  for  wood.  A  solution  of  it  spread  upon  pear  or 
cherry  wood,  for  a  few  minutes,  leaves  a  permanent  dark  brown 
color,  which,  after  careful  washing,  drying  and  oiling,  assumes 
a  reddish  tint  upon  being  polished. — N.  Jahrbt  Ph.  xx.  169. 
Persian  Insert  Powder.  Prof.  Koch,  states  the  insecticide 
power  of  this  article  is  due  to  a  volatile  oil,  residing  in  the 
pollen  of  the  flowers  N.  Jahrb.  Ph.  xx.  155. 
Rendering  bitUr  substances  tasteless.  The  addition  of  a  small 
quantity  of  chloroform  to  bitter  draughts  has  been  recommended 
as  a  means  of  facilitating  their  administration.  The  anaesthetic 
power  of  the  chloroform,  being  exerted  upon  the  organs  of  taste, 
deadens  their  perceptions.  A  drop  of  chloroform  spread  upon 
the  tongue  before  tasting  such  medicines,  is  suggested  as  equally 
satisfactory. — JV.  Jahrb.  Ph.  xx.  157.  , 
Preparation  of  Prussia  Acid.  Messrs.  Bussy  &  Buignet 
have  arrived  at  the  following  conclusions  in  regard  to  the  pre- 
paration of  this  acid  : — 
1.  In  the  process  of  Gea  Pessina,  the  quantity  of  hydrocy- 
