Am.  Jour.  Pharm.  \ 
July,  1876.  J 
Varieties. 
327 
VARIETIES. 
New  Crystallised  Hydrate  of  Hydrochloric  Acid.  By  I.  Pierre  and 
E.  Puchot. — Strong  commercial  hydrochloric  acid  may  be  maintained  at  a  very  low- 
temperature  without  any  change  ;  but  when  into  the  cooled  liquid  a  continuous 
current  of  nearly  dry  hydrochloric  acid  gas  is  passed,  an  abundant  deposition  of 
crystals  soon  occurs,  and  at  the  same  time  the  temperature  rises  from  —  220  to  — 
1 8°,  remaining  stationary  at  this  last  point  during  the  formation  of  the  crystals. 
These  crystals  decompose  rapidly  in  the  air,  emitting  white  fumeb ;  they  very 
quickly  dissolve  in  water  at  ordinary  temperatures,  but  at  —  180  the  solution  is  ef- 
fected very  slowly.  Analytical  results  lead  the  authors  to  assign  for  their  compo- 
sition the  formula  HC1.2H20. 
They  find  that  mixtures  of  snow  and  ordinary  hydrochloric  acid  constitute 
powerful  and  economical  refrigerants.  With  2  parts  of  snow  to  1  part  of  acid  a 
lowering  of  the  temperature  to  —  320  is  readily  obtained. —  Journ.  Chem.  Soc. 
Influence  of  various  Solutions  upon  the  Rusting  of  Iron.  By  A. 
Wagner. — Details  are  given  of  experiments  made  upon  strips  of  iron  which  were 
acted  upon  by  water  containing  various  salts,  in  presence  of  air  free  from  carbon 
dioxide,  and  of  air  containing  that  gas  at  various  temperatures,  and  also  in  sealed 
tubes,  from  which  air  was  expelled. 
The  general  results  were  that  pure  water  in  presence  of  air,  causes  iron  to  rust  ; 
that  if  carbon  dioxide  \i  also  present,  the  rusting  is  more  rapid  ;  that  the  production 
of  rust  is  materially  increased  by  the  chlorides  of  magnesium,  ammonium  sodium, 
potassium,  barium  and  calcium,  the  first  mentioned  being  most  active  in  this  respect ; 
that  iron  immersed  in  evaporated  river-water  rusts  more  slowly  than  iron  in  distilled 
water  ;  that  the  presence  of  oils  or  fats  greatly  diminishes  the  rapidity  of  rusting  5  that 
alkalies  prevent  the  rusting  entirely  Magnesium  chloride  solution  in  the  absence  of 
air  attacked  iron  at  a  temperature  of  about  ioo0;  chlorides  of  sodium,  potassium, 
barium,  and  calcium  were  without  action  under  the  same  circumstances.  The  origi- 
nal paper  must  be  consulted  for  details  and  measurements.  Journ.  Chem.  Soc.  [Lond.] 
On  the  Active  Constituent  of  Ergot  of  Rye.  By  R.  Buchheim. — 
According  to  the  author's  experiments,  the  active  constituent  of  ergot  (ergotin)  is 
a  body  closely  resembling  animal  gelatin.  It  is  easily  soluble  in  cold  water,  and 
is,  therefore,  contained  in  the  cold  aqueous  infusion  of  ergot.  Like  gelatin,  it 
gives  precipitates  with  phenylsulphuric  acid,  tannic  acid,  and  chlorine.  It  cannot, 
however,  be  completely  precipitated  by  tannic  acid.  It  is  formed  by  the  action  of 
the  mycelium  of  a  fungus  on  the  gluten  of  rye,  by  which  action  the  gluten  under- 
goes a  series  of  transformations,  terminating  in  its  conversion  into  leucin,  ammonia,, 
and  trimethylamin.  The  decomposition  of  gluten  under  the  influence  of  the 
fungus  is,  therefore,  analogous  to  the  putrefaction  of  albumin.  In  both  cases 
albuminous  substances  undergo  a  series  of  transformations  different  from  that 
which  occurs  in  the  healthy  animal  organism,  and  the  products  formed  have,  in 
