Sulphites. 
i  Am.  Jour.  Pliarm. 
1      March,  1890. 
It  would  seem  that  in  chloralamid  we  have  a  safe  hypnotic,  which 
hardly  ever'  has  any  depressing  effects,  which  does  not  produce 
indigestion,  and  very  rarely  gives  rise  to  any  unpleasant  results. 
We  do  not,  of  course,  yet  know  what  harm  may  result  from  its  pro- 
longed use.  References  to  those  authors  who  have  studied  the 
chemistry  and  physiological  action  of  the  drug  will  be  found  recorded 
by  Leech,  Paterson,3  and  in  a  leading  article  in  the  Therapeutic 
Gazette,  for  September,  1889.  Rabaw4  considers  45  grains  of  chlor- 
alamid to  be  equivalent  to  30  grains  of  chloral.  Chloralamid  has 
been  used  successfully  as  an  enema  by  Peiper.5 
SULPHITES.1 
By  P.  J.  Hartog. 
Normal  potassium  sulphite  is  obtained  by  dissolving  100 
grams  of  potassium  hydroxide  in  200  cc.  of  water  free  from 
oxygen,  saturating  with  sulphurous  anhydride,  and  then  adding 
a  further  quantity  of  100  grams  of  potassium  hydroxide  dissolved 
in  as  little  water  as  possible.  The  solution  is  evaporated  in  a 
vacuum,  and  the  crystals  are  drained  on  cotton  wool  in  an 
atmosphere  of  nitrogen.  Since  the  salt  is  less  soluble  in  hot 
water  than  in  cold,  it  is  advisable  to  keep  the  funnel  warm 
when  collecting  the  crystals.  The  sulphite  is  thus  'obtained  in 
small,  anhydrous,  hexagonal  prisms  with  basal  modifications.  It  is 
deliquescent,  but  oxidizes  less  rapidly  than  its  solution ;  heat  of 
dissolution  —  175  Cal.  • 
Normal  sodium  sulphite  is  obtained  in  the  same  way  in  anhydrous 
crystals  of  the  same  form,  always  mixed,  however,  with  a  certain 
proportion  of  the  heptahydrated  salt;  heat  of  dissolution  +  271. 
Sodium  potassium  sulphite,  NaKS03,  is  obtained  in  crystals, 
which  resemble  those  of  the  simple  anhydrous  salts,  by  adding 
potassium  hydroxide  to  sodium  anhydrosulphite.  When  the  solu- 
tion of  the  double  sulphite  has  been  partially  oxidized,  and  is  then 
gradually  concentrated,  the  crystals  which  separate  are  first  hepta- 
3  Lancet,  October  26,  1889. 
4  Centralblatt  fur  Nervenheilkunde,  August  1,  1889. 
5  Deutsche  Med.  Woch.,  Augusts,  1889. 
1  Compt.  rend.,cvx;  reprinted  from  four.  Chem.  Soc,  Dec,  1889,  p.  1106. 
■Compare  also  Amer.  Jour.  Phar.,  1889,  p.  584. 
