16  Gleanings  from  the  German  Journals.  {Am"/a0nuyiSoarm' 
vided.  Chemically  pure  ether  may  best  be  prepared  by  the  addition 
of  7  to  9  gm.  phenyl-hydrazin  to  5  kilos,  ether  and  subsequently 
rectifying ;  good  results  may  also  be  obtained  by  treating  the  ether 
with  a  strong  potassium  hydrate  solution  and  rectifying ;  this  latter 
method  is  at  present  practically  employed. — Th.  Poleck  and  K. 
Thtimmel,  Arch,  der  Pharm.,  1889,  961. 
Dispensing  of  Thymol  Powders. — If  thymol  be  powdered  in  a  porce- 
lain mortar  the  thymol  becomes  so  highly  electrified  as  to  adhere  pro- 
vokingly  to  all  substances  with  which  it  comes  in  contact ;  it  some- 
what deports  itself  like  a  very  deliquescent  substance.  F.  Sengewitz 
overcomes  the  difficulty  by  powdering  in  an  iron  mortar,  using  small 
quantities  at  a  time  and  exerting  little  pressure. — Pharm.  Ztg.,  1889r 
706. 
Ethyl  bromide  has  lately  been  so  successfully  used  in  dental  opera- 
tions that  preference  is  given  to  it  over  chloroform,  nitrogen  monoxide 
and  cocaine  salts  ;  its  success  is  ascribed  to  the  purity  of  the  chemical 
as  at  present  made  from  alcohol,  potassium  bromide  and  sulphuric 
acid.  It  resembles  chloroform  in  that  the  pure  substance  is  easily 
decomposable,  and  the  addition  of  one  per  cent,  of  alcohol  or  ether 
retards  or  prevents  the  decomposition.  The  specific  gravity  of  pure 
ethyl  bromide  at  15°C.  is  1*4735,  while  that  containing  one  per  cent, 
alcohol  is  1*457  at  15°  C.  Tests  of  purity  are:  1.  The  absence  of 
color  when  shaken  with  an  equal  volume  of  concentrated  sulphuric 
acid,  and  2.  water  agitated  with  ethyl  bromide,  after  separation,  should 
not  react  acid,  nor  give  a  turbidity  with  silver  nitrate  solution. — Dr. 
H.  Thorns,  Pharm.  Ztg.,  1889,  705. 
Cocaine  chr ornate, — Dr.  Karl  Mezger  uses  the  formation  of  this  salt 
as  a  test  for  cocaine  in  as  dilute  solutions  as  1:1,000.  The  test  of 
identity  is  applied  by  dissolving  0*05  gm.  cocaine  hydrochlorate  in  5 
cc.  water  and  adding  five  drops  of  a  five  per  cent,  chromic  acid  solu- 
tion ;  each  drop  forms  a  decided  precipitate,  which,  however,  again 
dissolves  j  after  the  addition  of  1  cc.  pure  concentrated  hydrochloric 
acid  an  immediate  orange-yellow  precipitate  of  cocaine  chromate  should 
appear  —Pharm.  Ztg.,  1889,  697. 
Soaps. — The  preparation  of  soap  always  requires  the  use  of  an 
excess  of  alkali  which  should  afterwards  be  removed  by  salting  out 
the  soap ;  to  obtain  a  neutral  soap  this  operation  must  be  repeated 
several  times,  and  the  soap  so*  obtained  always  retains  some  of  the 
alkaline  chloride.    Dr.  E.  Geissler  in  a  paper  on  this  subject  recom- 
