294 
Chemical  Notes. 
j  Am  Jour.  I'harm^ 
(      June,  1881. 
the  production  of  cyanides  of  the  alkalies  and  alkaline  earths.  Start- 
ing out  with  the  cyanide-formation  in  the  Leblanc  process,  he  finds  as- 
the  results  of  his  studies  that  the  cyanides  of  the  alkali  metals  as  well 
as  of  the  alkaline  earths  are  formed  when  : 
1.  Their  oxides,  hydrates  or  carbonates  are  ignited  with  charcoal  in 
a  nitrogen  atmosphere,  in  which  case  an  addition  of  finely  divided 
iron  is  especially  helpful; 
2.  When  the  sulphates  or  sulphides,  mixed  with  calcium  carbonate 
and  charcoal,  are  ignited  in  a  nitrogen  atmosphere,  either  with  or 
without  the  addition  of  iron  ; 
3.  When  the  sulphates  or  sulphides,  mixed  with  charcoal  and  a 
metal  which  has  when  heated  a  strong  affinity  for  sulphur,  such  as 
iron,  zinc,  copper,  are  ignited  in  a  nitrogen  atmosphere ; 
4.  When  the  sulphides  of  the  alkaline  earths  are  changed  into- 
oxides  or  carbonates  by  ignition  with  hydrocarbons  and  then  treated 
as  in  section  1. 
The  inventor  proposes  the  following  process :  Wood  charcoal,  coke,, 
sawdust  and  so  forth  are  saturated  with  a  solution  of  the  alkaline  or 
alkaline-earth  salt.  Or  pulverized  charcoal  is  saturated  with  the  solu- 
tion and  a  mass  is  then  made  up  with  sawdust  or  half-charred  wood. 
The  iron  is  incorporated  as  metallic  powder,  or  the  charcoal  having 
been  saturated  with  ferric  chloride  or  sulphate  solution,  is  dried  and. 
ignited  in  a  current  of  steam. 
The  materials,  so  prepared,  are  ignited  in  retorts  into  which  nitro- 
gen gas  is  conducted.    This  nitrogen  gas  is  prepared  by  passing 
atmospheric  air  through  a  series  of  tubes  in  which  it  gives  up  its 
oxygen  to  alkaline  sulphides,  such  as  barium  sulphide,  solutions  of  - 
Avhich  saturate  various  porous  materials. — Ibid.,  pp.  117-118. 
Organic  Chemistry. —  On  the  Change  of  Glucose  into  Dextrine. — 
In  the  year  1872,  Musculus  prepared,  by  the  action  of  concentrated 
sulphuric  acid  upon  glucose,  a  compound  which  he  considered  to  be  a 
dextrine.  Later,  Gautier,  by  the  action  of  hydrochloric  acid  gas  upon 
glucose,  prepared  a  compound,  Ci2H220jj,  and  Musculus,  in  connection 
with  Meyer,  now  repeats  his  experiments  with  sulphuric  acid  for  the 
sake  of  comparison.  Pure  glucose  (30  grams)  was  fused  in  a  chloride 
of  calcium  bath,  and  after  this  had  cooled  an  equal  weight  of  concen- 
trated sulphuric  acid  was  added  in  4  or  5  successive  portions.  The 
mass,  which  was  kept  stirred,  must  not  rise  above  60°.  It  was  then 
treated  with  absolute  alcohol  (800  grams),  and  the  filtrate  allowed  to 
