24  Brom  ide  of  Calcium .  { AMjaJn0Df  •  *****  ■ 
hoi  is  exhausted,  which  may  be  known  by  the  dense  red  fumes  evolved 
from  the  retort.  The  distilled  product  exceeds  in  bulk  the  amylic 
alcohol  used,  and  is  the  impure  nitrite  of  amyl.  This  is  washed  with 
solution  of  Na  H  0  to  remove  the  HON  and  other  free  acids  present  , 
and  rectified  over  fused  K2C  03  to  get  rid  of  moisture.  The  portion 
which  distils  between  95°  and  100°  C.  is  collected  as  nitrite  of  amyl, 
sufficiently  pure  for  medicinal  use. 
It  has  several  times  been  stated  that  nitrite  of  amyl  produces  vio- 
lent headache,  and  also  coughing  and  irritation  of  the  larynx ;  this,  I 
think,  must  be  due  to  its  insufficient  purification.  The  presence  of 
HON  and  undecomposed  amylic  alcohol  would,  I  think,  account  for 
this ;  no  such  effect  was  produced  on  myself  with  the  purified  nitrite. 
Mr.  Umney  has  shown,  in  an.  article  in  the  Pharmaceutical  Journal 
of  November,  1870,  that  the  samples  then  met  with  were  very  impure. 
— Pharm.  Journ.  and  Trans.,  Nov.  25,  1871. 
NOTE  RELATIVE  TO  THE  BROMIDE  OF  CALCIUM. 
By  William  A.  Hammond,  M.  D. 
Bromide  of  calcium  is  a  white  crystalline  substance,  very  soluble 
in  water,  and  readily  decomposing  on  exposure  to  the  atmosphere 
for  a  few  minutes.  The  aqueous  solution  is  at  first  colorless,  but  it 
soon  becomes  tawny  from  a  portion  of  the  bromide  being  set  free. 
Its  taste  is  similar  to  that  of  the  bromide  of  potassium,  though  some- 
what more  pungent  and  disagreeable. 
The  formula  of  bromide  of  calcium  is  BrCa,  and  its  combining 
equivalent  is  98  (Br.  78,  Ca.  20  r=  98)  ;  100  grains,  therefore,  con- 
tain about  79.5  grains  of  bromine. 
Desiring  to  test  the  therapeutical  value  of  this  compound,  I  de- 
sired Dr.  Neergaard  to  procure  it.  During  the  last  few  months  I 
have  used  it  in  a  number  of  cases  in  which  the  bromides  were  indi- 
cated, and  have  become  satisfied  of  its  great  efficiency  as  a  medicinal 
agent. 
The  dose  is  from  fifteen  to  thirty  grains  or  more  for  an  adult.  It 
is  especially  useful  in  those  cases  in  which  speedy  action  is  desirable, 
as,  owing  to  its  instability,  the  bromine  is  readily  set  free,  and  its 
peculiar  action  on  the  organism  obtained  more  promptly  than  when 
either  of  the  other  bromides  is  administered.  Chief  among  these 
effects  is  its  hypnotic  influence,  and  hence  the  bromide  of  calcium  is 
