406 
GLEANINGS  FKOM  THE  GERMAN  JOURNALS. 
Fluorine  in  the  ashes  of  Lyeopodium  complanatum  was  dis- 
covered by  Prince  Salm-Horstmar.  The  fresh  plant  yielded  6 
per  cent,  ashes,  100  grms.  of  which  contained  4  grm.  Fl,  or  the 
part  soluble  in  HCl  -27,  the  insoluble  portion  (silica)  -15  grm. 
Fl.  In  oats  and  straw  he  found  baryta. — (Poggend.  Ann.  cxi. 
329.    Buchn.  N.  Rep.  x.  38,  79.) 
Estimation  of  free  Carbonic  Acid  in  water. — Prof.  Dr.  Petten- 
kofer  mixes  100  c.  c.  m  with  3  c.  c.  m.  of  a  nearly  concentrated 
solution  .of  chloride  of  calcium,  to  decompose  alkaline  carbonates, 
and  with  2  c.  c.  m.  of  a  saturated  solution  of  chloride  of  am- 
monium, to  retain  magnesia  in  solution,  and  finally  with  45  c.c.m. 
lime  water  of  known  strength.  In  12  hours  the  amorphous  car- 
bonate of  lime  becomes  crystalline  and  insoluble  ;  now  50  c.c.m. 
(one-third)  of  the  clear  liquid  is  neutralized  with  normal  oxalic 
"  acid,  and  another  third  may  be  used  for  a  controlling  second  ex- 
periment. The  difference  in  the  amount  of  acid  required  for 
neutralizing  this  mixture  and  the  original  lime  water,  indicates 
the  free  carbonic  acid,  that  is,  all  uncombined  acid,  and  all  over 
and  above  that  requisite  for  the  formation  of  monocarbonates. 
Waters  very  rich  in  carbonic  acid  are  previously  diluted  with  a 
known  proportion  of  boiled  distilled  water.— (Buchn.  IST.  Rep.  x. 
1-9.) 
Solubility  of  Sulphate  of  Ammonia. — Dr.  A.  Yogel  found  that 
1  part  of  this  salt,  dissolved  at  ordinary  temperature  in  1-3  p. 
water.— (Buchn.  K  Rep.  x.  9-11.) 
Conversion  of  Theobromina  into  Caffeina  Prof.  Strecker  has 
succeeded  in  this  conversion  by  heating  in  a  sealed  tube  the 
compound  of  theobromina  and  oxide  of  silver,  with  iodide 
of  methyle,  and  crystallizing  the  alkaloid  from  alcohol. 
C,ANA+A-gO+C,H,I  yield  C,,H,„N,0,+  HO+AgI. 
V  ^  ^  \  ^ 
Theobromina.  Caffeina. 
(Buchn.  K  Rep.  x.  32.) 
A  new  iodine  spring,  near  Partenkirchen,  on  the  foot  of  the 
Bavarian  Alps,  has  been  discovered.  Professor  Buchner  states 
that  it  contains  the  iodine  as  iodide  of  sodium,  somewhat  less 
than  the  celebrated  Heilbrunn  spring.    It  contains,  beside  this, 
