VARIETIES. 
467 
t)arictic0. 
On  the  Preparation  of  Subacetate  of  Lead  hy  the  Cold  Process.  By  M . 
Nerning.  When  this  preparation  is  made  with  heat,  the  acetate  of  lead 
is  liable  to  dissolve  excess  of  oxide  of  lead,  and  insoluble  basic  acetate  is 
thus  produced,  forming  a  white  flocculent  precipitate,  which  renders  the 
liquid  turbid.  To  obviate  this  inconvenience,  M.  Nerning  proposes  to 
operate  as  follows  : — Put  the  water,  litharge,  and  acetate  of  lead  into  a 
bottle,  and  let  them  stand,  with  frequent  agitation,  for  twenty-four  hours, 
then  filter.  The  solution  thus  obtained  answers  all  the  purposes  for 
which  it  is  required  in  pharmacy,  and,  if  kept  in  a  well-stoppered  bottle, 
it  will  remain  clear  even  when  kept  for  a  long  time. — Pharm.  Journ.y 
July  9,  1870, /rom  Journal  de  Pharmacie  et  de  Chimie  * 
The  Riga  Pine. — M.  Keller,  of  Darmstadt,  writing  in  '  Cosmos,'  says, 
that  what  is  known  outside  Russia  as  the  Riga  Pine,  [yielding  Riga  Bal- 
sam] and  which  has  been  praised  for  its  specially  good  qualities,  is  un- 
known by  any  distinctive  appellation  at  Riga,  and  is,  in  fact,  nothing 
more  than  the  ordinary  Pinus  sylvestris. — Pharm.  Journ.,  July  9,  1870, 
from  Athenaeum. 
Gonvertion  of  Angelic  into  Valerianic  Acid. — According  to  JafFe,  an- 
gelic acid  is  not  converted  into  valerianic  acid  by  means  of  hydriodic 
acid.  According  to  Ascher,  a  temperature  of  180'^  to  200°  0.  is  needed 
for  this  transformation,  which  does  not  take  place  at  low  temperatures^ 
By  heating  together  angelic  acid,  red  phosphorus,  and  hydriodic  acid  to 
180*°  to  200°  C,  for  the  space  of  eight  hours,  a  complete  transformation 
into  valerianic  acid  was  effected.  As  our  readers  will  know,  angelic  acid 
differs  from  valerianic  acid  by  two  equivalents  of  hydrogen,  which,  accord- 
ing to  the  foregoing  account,  it  acquires  from  the  hydriodic  acid. — Pharm, 
Journ.,  August  6,  1870. 
Hybridization  of  Ginchonoe. — At  the  March  meeting  of  the  Linnean 
Society  an  interesting  paper,  by  Mr.  Broughton,  chemist  to  the  Madras 
Government,  was  communicated  by  Mr.  Howard.  Mr.  Broughton  stated 
that  in  the  Madras  gardens  young  plants  were  growing  which  appeared 
t©  be  hybrids  between  C  succiruhra  and  G.  ojfficinalis.  In  Java  also  some- 
thing similar  has  occurred  between  G.  Calisaya  and  G.  Pahudiana  (=  G. 
Hasskarliana,  nov.  sp.  Miq,).    In  a  letter,  Dr.  de  Vrij  says  :— "  The  Ga- 
*The  editor,  in  a  note,  states  with  reference  to  this  process,  that  it  has  long  been 
adopted  in  the  military"  hospitals,  the  foliowiug  being  the  proportions  of  ingredients 
used :— Crystallized  acetate  of  lead  three  hundred  parts;  litharge,  in  fine  powder,  a 
hundred  parts;  distilled  water,  six  hundred  and  fifry  parts.  Put  them  into  a  bottle,  shake 
them  from  time  to  time,  and  at  the  expiration  of  six  or  eight  hours,  tilter. 
