Am.  Jour.  Phakj».  ) 
Aug.  1,  1872.  J 
Varieties. 
375 
way.  The  former  is  described  as  follows  :  When  one  equivalent  of  sulphuret 
of  sodium  is  mixed  and  fused  with  one  equivalent  each  of  caustic  soda,  hydrate 
of  lime  and  metallic  iron  (either  cast  or  malleable),  and  these  substances  heated 
to  redness,  the  sulphuret  of  sodium  is  completely  converted  into  caustic  soda, 
while  sulphuret  of  iron  is  simultaneously  formed.  This  reaction  is  explained 
by  the  author  as  follows :  The  water  of  the  hydrate  of  soda,  or  of  the  hydrate 
of  lime,  is  decomposed  by  the  iron  which  becomes  oxidized,  hydrogen  is  set 
free,  oxide  of  sodium  formed,  and  next  sulphuret  of  iron  ;  the  soda  is  separated 
from  the  last  named  substance  by  lixiviation  with  water.  As  regards  the  process 
by  the  wet  way,  the  author  converts  the  sulphuret  of  sodium  into  a  basic 
phosphate  of  soda  by  means  of  a  rather  circuitous  process  (scientifically  correct, 
but  not  well  adapted  for  industrial  application),  and  this  basic  phosphate  of 
soda  is  next  converted  into  caustic  soda  by  means  of  caustic  lime. — Ibid. ,  from 
Les  Mondes,  May  2. 
Influence  of  the  Potassa  and  Soda  Salts  upon  Alcoholic  Fermentation. — C. 
Knapp. — After  first  referring,  at  some  length,  to  the  researches  of  physiolo- 
gists on  the  action  of  the  potassa  salts  upon  the  animal  organism,  the  author 
details  at  length  a  series  of  experiments  made  with  the  view  to  ascertain  the 
difference  of  action — if  any — upon  the  process  of  fermentation  of  sugar  solu- 
tions to  which  yeast  is  added.  While  it  is  evident,  from  these  researches,  that 
potassa  salts  accelerate  the  fermentation,  while  soda  salts  are  inactive,  the 
mode  of  action  of  the  first- named  salts  is  not  precisely  clear. — Ibid.,  June  21, 
1872,  from  Ann.  d.  Chem.  a.  Pharm.,  1872,  N.  7. 
On  Sexbasic  Saccharate  of  Lime. — H.  Deon. — When  tribasic  saccharate  of 
lime  is  treated  with  alcohol  the  sexbasic  saccharate  is  obtained  by  elimination 
of  one  half  of  the  sugar,  exactly  in  the  same  way  as  by  treatment  of  the  mono- 
basic saccharate  with  alcohol  yields  the  bibasic  saccharate  ;  while  the  mono- 
basic and  tribasic  saccharates  contain  water,  the  bibasic  and  sexbasic  saccha- 
rates  contain  none.  The  reactions  are  thus  analogous,  and  may  be  expressed 
by  the  following  formulae  :  Oi2HnOn6CaO,  derived  from — 
2(0i2HiiOii3CaO4-HO)0i2HnOii20aO, 
derived  from  2(Ci2HiiOuCaO  +  HO) ;  when  sexbasic  saccharate  is  combined 
with  two  equivalents  of  sugar,  bibasic  saccharate  is  obtained, — and  when  two 
equivalents  of  sugar  are  added  to  tribasic  saccharate,  monobasic  saccharate  is 
formed.— Ibid.,  June  28,  1872. 
Digestion  of  Calomel — In  his  recent  lecture  on  "  Diet  and  Medicine/'  Dr. 
Symes  Thompson  showed  that  some  drugs  undergo  a  process  of  solution  within 
the  body,  analogous  to  that  which  food  passes  through  under  the  influence  of 
the  digestive  juices.  With  the  assistance  of  Professor  Heaton  he  demon- 
strated Tuson's  experiment  on  calomel.  In  one  vessel  (a)  calomel  and  hydro- 
chloric acid  were  placed,  and  in  another  (b)  calomel,  acid  and  pepsine.  After 
digestion  for  two  or  three  hours,  at  the  temperature  of  the  blood  (care  being 
taken  that  the  heat  should  not  rise  above  140°  Fahr.),  the  contents  of  both 
vessels  were  thrown  on  filters.  The  filtered  liquid  from  the  second  (b)  gave  a 
black  precipitate  with  sulphuretted  hydrogen,  showing  that  pepsine  had  ren- 
