20 
GLEANINGS  FROM  GERMAN  JOURNALS. 
posed  to  sunlight  undergoes  decomposition  ;  chlorine  is  evolved 
and  soon  hydrochloric  acid  is  formed ;  diffused  daylight  has  ap- 
parently no  influence,  but  it  is  better  to  keep  it  in  the  dark.  The 
best  means  of  preservation  is  an  addition  of  half  to  one  per  cent, 
of  absolute  alcohol ;  such  a  chloroform  remains  comparatively 
unaffected  by  direct  sunlight.  Commercial  chloroform  has  had 
this  addition  for  many  years,  and  no  bad  effects  have  been 
observed  in  consequence  thereof.*  For  medicinal  chloroform 
the  specific  gravity  of  1*480 — 1*485  is  recommended. 
The  expansion  of  pure  chloroform,  according  to  the  author's 
experiments,  is  about  '002  for  every  degree  centesimal ;  we  give 
from  his  table  the  spec,  gravity  at  the  following  temperatures 
only:  0°  C.  1.525,  5°  C.  1*518,  10°  C.  1-510,  L5i°  C.  1*500, 
20°  C.  1*491,  25°  C.  1*481.    Ihid.  545-558. 
Cypripedium  among  Senega  has  been  observed  for  several 
years,  by  Dr.  F.  A.  Fllickiger,  and  was  recognized  as  such  by 
A.  E.  Ebert,  of  Chicago.  Dr.  F.  describes  the  anatomical 
structure  of  the  adulteration,  which  agrees  with  specimens  of  the 
rhizome  and  roots  obtained  by  him  from  Professor  Procter. 
Ihid.  565-569,  from  Schweiz.  Wochenschr.  f.  PJiarm. 
Nitrite  of  potassa  in  saltpeter. — Prof.  Boettger  states  that 
nearly  all  commercial  saltpeter  contains  notable  quantities  of 
nitrite  of  potassa,  originating  undoubtedly  from  the  nitrate  of 
soda,  which  contains  considerable  nitrite.  Saltpeter  is  now 
usually  prepared  by  decomposing  this  salt  with  chloride  of  potas- 
sium, and  the  nitrite  remains  mixed  with  it  in  consequence  of  in- 
suflScient  recrystallization.    Ibid,  570. 
New  test  for  nitrates  and  chlorates  proposed  by  Dr.  Braun. — 
Professor  Boettger  puts  into  a  porcelain  capusule  1  C.  C.  pure 
concentrated  sulphuric  acid,  then  drop  by  drop  J  C.  C.  solution 
of  sulphate  of  anilina,  then  the  substance  to  be  tested ;  the 
whole  is  slowly  stirred  with  a  glass  rod.  The  presence  of  minute 
quantities  of  a  nitrate  will  produce  zones  of  a  beautiful  red 
color,  caused  by  the  formation  of  fuchsina.    A  chlorate  will 
*  It  will  be  observed  that  Mr.  Rump's  results  are  identical  with  mine, 
obtained  since  1865,  and  an  account  of  which  is  found  in  this  journal, 
1867,  p.  73  and  1868,  p.  289.— J.  M.  M. 
