AmjInU,ri8P78arm  }  Pharmaceutical  Colleges  and  Associations.  41 
to  some  extent,  be  separated  with  the  nitrite  of  ethyl.  Regarding  pure  nitrite  of 
ethyl,  the  speaker  hoped  that  it  would  not  be  demanded  of  pharmacists,  and  con- 
sidered it  extremely  undesirable  the  public  should  have  undiluted  chemical  principles 
of  such  great  activity  and  danger  placed  in  their  hands. 
Mr.  R.  H.  Davies,  in  preparing  nitrite  of  ethyl  had  generated  nitrous  acid  from 
nitric  acid  and  arsenic,  and  followed  Liebig's  process,  of  which  Mr.  Williams1  is  an 
improvement.  He  had  observed  a  separation  of  about  5  per  cent,  from  an  alcoholic 
solution  containing  10  per  cent,  of  commercial  pure  aldehyd,  on  being  treated  with 
solution  of  calcium  chloride. 
Mr.  Umney  had  worked  with  the  Pharmacopoeia  process  on  a  large  scale,  having 
never  less  than  tour  gallons  of  spirit  in  the  still,  and  met  with  no  difficulty  in  obtain- 
ing a  concentrated  solution  of  hyponitrous  ether  by  that  process.  Working  with 
such  quantities  some  extra  attention  is  required  to  moderate  the  action. 
Prof.  Redwood  had  also  seen  the  process  worked  for  many  years  in  quantities 
quite  as  large  as  those  mentioned.  The  distillate  would,  with  solution  of  calcium 
chloride,  separate  from  38  to  40  per  cent,  of  etherial  liquid,  probably  about  one- 
half  of  which  was  nitrite  of  ethyl.  He  felt  that  the  process  which  he  had  been  the 
means  of  introducing,  was  the  only  known  process  of  producing  sweet  spirit  of 
nitre  of  a  tolerably  definite  composition. 
Mr.  Williams  stated  that  his  paper  referred  not  to  spirit  of  nitre,  but  to  solutions 
of  pure  nitrite  of  ethyl  in  absolute  alcohol.  Aldehyd  usually  contains  acetic  ether 
and  acetone  ;  pure  aldehyd  would  not  separate  with  chloride  of  calcium. 
Tke  color  of  podophyllum  resin  was  the  title  of  a  paper  presented  by  Dr.  A.  Senier 
and  A.  J.  G.  Lowe.  The  authors  observed  that  the  color  ot  the  resin  is  affected  by 
the  relative  proportion  of  water,  an  increase  of  which  renders  it  lighter  and  more 
yellowish,  and  that  hot  water  darkens  the  resin  by  partial  fusion.  The  authors 
found  several  samples  to  be  free  from  alkaloid.  Alum  water  gives  a  bright 
yellow  resin  and  increases  the  ash  j  prepared  with  water  or  acidulated  water,  only 
•1  per  cent,  of  ash  was  found  5  in  8  commercial  samples  it  varied  between  -2  and  4*1 
per  cent  The  authors  conclude  that  the  variations  of  shade  and  color  do  not  affect 
the  physiological  activity  of  the  resin. 
Mr.  Martindale  thought  that  the  part  of  podophyllum  resin  insoluble  in  ether  was 
of  a  bright-yellow  color,1  and  would  partly  account  for  the  difference  of  color. 
Mr.  Harold  Senier  read  a  paper  on  Rheum  officinale  gro^wn  in  England.  The  root 
yields  a  brighter  powder  than  East  Indian  rhubarb  and  Rheum  rhaponticum,  and 
also  a  slightly  darker  infusion.  By  the  officinal  process  for  extract  of  rhubarb  it 
yielded  25,  the  others  45  and  29  per  cent,  respectively.  By  rectified  spirit  17,  38 
and  21  per  cent,  of  extract  was  obtained,  and  this  yield  is  regarded  as  a  more  relia- 
ble basis  for  comparison.  The  three  kinds  yielded  4-66,  i2-72  and  7  9  per  cent,  of 
ash.  The  results  point  to  the  conclusion  that  the  root  of  Rheum  officinale  is  of  less 
commercial  value  than  that  of  Rh.  rhaponticum,  and  are  what  one  might  expect 
from  the  rapid  growth  of  the  root,  this  particular  sample  being  produced  in  about 
three  years.    The  extract  was  found  to  be  decidedly  cathartic  in  10  grain  doses. 
False  Angostura  Bark  and  Brucia.    By  W.  A.  Shenstone. — The  author  found  the 
This  does  not  agree  with  our  observation.    See  also  "Am.  Jour.  Phar.,"  1877,  p.  549  — Editor. 
