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GLEANINGS  FROM  GERMAN  JOURNALS. 
of  borax  are  dissolved  in  twenty  of  hot  water;  the  solution  is 
evaporated  and  the  residue  powdered. 
Tartarus  ferratus  is  our  ferri  et  potassse  tartras.  The  Swiss 
pharmacopoeia  contains  a  pure  and  a  crude  salt ;  the  latter  made 
from  crude  tartar,  and  designed  chiefly  for  external  use  in  baths. 
In  the  process  for  chloride  of  zinc,  our  pharmacopoeia  assumes 
the  presence  of  iron  as  an  impurity,  and  uses  chalk  to  separate 
it,  thereby  contaminating  the  preparation  with  a  little  chloride 
of  calcium.  The  metal  zinc,  however,  is  directed  to  be  entirely 
free  from  iron.  The  Swiss  pharmacopoeia  uses  oxide  of  zinc 
and  pure  muriatic  acid,  and  thereby  avoids  the  contamination 
and  an  inconsistency.  The  acetate  and  sulphate  of  zinc  are 
likewise  very  properly  prepared  from  the  oxide. 
Z  in  cum  cyanatum  (not  to  be  confounded  with, the  non-poison- 
ous ferrocyanide)  is  made  by  passing  hydrocyanic  acid  into  a 
solution  of  acetate  of  zinc.  The  ferrocyanide  is  obtained  by 
double  decomposition. 
Of  the  valerianates,  the  zinc  salt  only  is  officinal. 
(To  be  continued.) 
GLEANINGS  FROM  GERMAN  JOURNALS. 
By  John  M.  Maisch. 
Diabetes.  M.  Pettenkofer  and  C.  Voit  observed  that  a  patient 
who  secreted,  by  the  urine,  in  a  day,  644  grammes  of  sugar,  ex- 
haled through  skin  and  lungs  795  grammes  carbonic  acid,  and 
inhaled  792  grammes  oxygen,  quantities  agreeing  with  those  of 
a  healthy  adult  under  ordinary  circumstances.  But  the  large 
quantity  of  food  consumed  by  the  diabetic  patient  would  pro- 
duce in  a  healthy  man  a  much  larger  exhalation  of  carbonic  acid, 
while  the  food  which  is  sufficient  for  the  latter  would  cause  with 
the  former  a  diminished  use  of  oxygen  and  a  diminished  separa- 
tion of  carbonic  acid — that  is  to  say,  he  would  be  like  a  healthy 
person  suffering  from  hunger.  Pure  meat  and  fat  without  carbo- 
hydrates, used  as  food,  may  diminish  the  secretion  of  sugar  to 
300  grammes,  but  do  not  cause  its  disappearance.  In  this 
case  the  sugar  must  be  produced  from  the  fat,  and  from  the  fatty 
body  generated  by  the  splitting  of  the  albumen. 
