456 
CHLORAL. 
Inasmuch  as  the  production  of  these  compounds  takes  place 
without  formation  of  any  bye-products,  analysis  of  them  ap- 
peared to  be  unnecessary.  We  have,  however,  taken  the  vapor- 
densities  of  some  of  them,  and  found  that,  like  chloral-hydrate 
itself,  they  have  only  half  the  condensation  indicated  by  their 
formulae. 
With  the  ethers  of  the  alcohol-radicals  chloral  does  not  com- 
bine. The  compound  of  chloral  and  ethylic  alcohol. boils  at  115° 
to  116°  C,  and  solidifies  at  40°  C,  becoming  crystalline.  At 
40°  C.  (in  the  fluid  condition)  its  sp.  gr.  is  1-143. 
In  cold  water  it  dissolves  only  slowly,  but  on  warming, 
the  solution  is  complete.  In  ether,  alcohol,  acetic  ether,  and 
petroleum,  it  is  easily  soluble ;  and  on  cooling  the  hot  concen- 
trated solution,  it  crystallizes  out  in  long  beautiful  needles. 
The  methylic  compound  resembles  the  ethylic  compound  very 
closely.    It  boils  at  98°  C. 
The  amylic  compound  boils  at  143°  C,  and  at  25°  C.  has  a 
sp.  gr.  of  1-2340.  At  25°  C.  it  solidifies  to  a  crystalline  mass, 
which  is  soluble  in  ether,  alcohol,  and  petroleum.  From  the 
last-named  solvent  it  is  capable  of  crystallizing  in  long  tufts  of 
needles.  Only  on  prolonged  boiling  fvith  water  is  the  decompo- 
sition into  chloral  and  amylic  alcohol  complete. 
Chloral-mercaptide,  chloral,  and  mercaptan  combine  with  great 
evolution  of  heat,  and  form  a  crystalline  compound,  soluble  in 
ether,  alcohol,  sulphuret  of  carbon,  and  capable  of  crystallizing 
easily  out  of  its  solutions  in  these  solvents. 
We  can  easily  understand  that  the  alcohol-compound  has  been 
often  taken  for  the  hydrate  of  chloral,  and  that  the  hydrate  has 
been  often  contaminated  with  the  alcoholate. 
It  appears  to  us  to  be  especially  interesting  to  study  the 
physiological  characters  of  the  alcohol-compounds  ;  according  to 
0.  Liebreich,  the  physiological  efi'ects  of  the  alcoholate  differ 
essentially  from  those  of  hydrate.  In  preparing  the  hydrate 
for  medicinal  use,  one  of  the  main  points  to  be  attended  to  is  its 
freedom  from  alcoholic  compounds.  Pure  hydrate  of  chloral 
boils  at  95°  C,  as  we  have  ascertained  by  numerous  experi- 
ments.— Pharm.  Journ.^  July  30, 1870, /rom  Buchners  "  Reper- 
torium  far  JPha7'macie,'' ISIO. 
