Am.  Four.  Pnanu.  » 
mv.,  1880.  J 
Reviews^  etc. 
iMoens,  Guillermond,  Carles,  Stoeder,  Cleaver  an  J  others,  and  proposes  a  process 
<for  the  valuation  of  cinchona  bark,  ba-;ed  upon  thit  recoain ended  by  De  Vrij,  and 
of  which  the  following  is  an  outline:  2  grams  of  the  mixed  alkaloids  are  dissolved 
as  acetates  in  30  cc.  of  water  and  the  solution  mixed  with  i  gram  of  Rochelle  salt 
and  well  stirred.  The  precipitate  contains  quinia  and  cinchonidia  tartrates,  which 
are  dissolved  in  20  parts  of  90  per  cent,  alcohol  acidulated  with  i-6  per  cent,  sul- 
(phuricacidj  in  this  solution  the  quinia  is  estimated  by  iodosulphate  of  chinoidin, 
and  the  cinchonidia  by  the  difference  of  the  weights  of  the  mixed  tartrates  and  of 
'the  quinia  tartrate.  The  filtrate  from  the  precipitated  tartrates  yields  with  sodium 
•  iodide  a  precipitate  of  quinidia  hydriodate,  and  from  the  filtrate  the  remaining 
alkaloids  are  recovered  by  soda,  dried  and  exhausted  by  absolute  ether,  which  dis- 
solves the  amorphous  alkaloid  with  small  quantities  of  quinia.  The  insoluble  por- 
•tion  is  washed  with  water  to  remove  soda,  and  the  residue  weighed  as  cinchonia.  In 
the  details,  given  by  the  author  the  alkaloidal  compounds  remaining  dissolved  in 
the  mother- liquors  and  wash-waters  are  likewise  estimated. 
.Vergleichende  Untersuchung  einiger  indischen  Handelssorten  des  arabischen  Gummi, 
und  der  ivichtigsten  Handelssorten  des  Traganth  und  seiner  Surrogate.    By  Emil 
Masing.  Dorpat. 
•Comparative  examination  of  several  East  Indian  varities  of  gum-arabic,  and  of  the 
most  important  commercial  varieties  of  tragacanth  and  its  substitutes. 
The  two  essays  are  reprinted  from  "  Archiv  der  Pharmacie."  The  author  has 
^determined  for  the  gums:  Moisture,  solubility  in  water,  ash,  HCl  required  for  neu- 
tralizing ash,  and  the  behavior  of  the  gum  solution  to  potassium  silicate,  potassium 
stannate,  neutral  and  basic  lead  acetate,  neutral  copper  acetate  and  ferric  chloride. 
The  tragacanths  were  examined  for  moisture,  ash,  HCl  for  neutralizing  the  ash, 
amount  perfectly  soluble  in  water  on  treating  -5  gram  with  100  cc.  of  water,  and 
volume  of  sediment  deposited  in  this  solution  after  standing  for  two  days. 
Versuche  uber  die  Wirkung  des  Pepsins  auf  einige  animalische  und  ^egetabilische  Nah- 
rung->mitteL    Von  Friedrich  Kessler     Dorpat,  1880.     Pp.  48. 
JExperiments  on  the  effect  of  pepsin  upon  various  animal  and  vegetable  victuals. 
A  large  number  of  experiments  made  for  the  purpose  of  determining  the  com- 
parative digestibility  of  numerous  substances  in  the  raw  state  and  variously  prepared. 
Beitrdge  zur  Kenntniss  der  Aloe.    Von  Carl  Treumann.     Dorpat,  1880.    Pp.  78. 
Contributions  to  our  knowledge  of  aloes. 
From  these  investigation  we  mention  the  composition  of  the  various  aloins  as 
determined  by  the  author:  Barbaloin  C^gH.gO.^Q,  Capaloin  C^gH^gO^^,  Socaloin 
^45^52^20'  Nataloin  C^-Hj-O.^q  and  Curagaoaloin  C^^H^qC^q.  The  purgative  proper- 
ties of  aloes  are  due  to  aloin  as  well  as  to  its  oxidation  products 5  the  latter  being 
the  less  active,  the  more  they  differ  from  the  former.  While  nataloin  is  without 
medicinal  value,  the  doses  of  the  other  aloins  are  as  follows:  Capaloin,  it.  to  •16 
gram  j  barbaloin,  15  to  -2  gram  5  socaloin,  -2  to  -25  gram  and  Curagaoaloin  '25  to 
•3  gram. 
