GLEANINGS  FROM  FOREIGN  JOURNALS. 
29 
side  below  the  tubulus,  and  fits  into  an  adapter-tube  attached 
to  an  upright  cylindrical  condenser  made  of  brass,  which  ends 
both  above  and  below  into  a  narrow  tube,  the  latter  to  carry  off 
the  condensed  products,  the  other  as  a  safety-tube.  The  con- 
denser is  enclosed  in  a  brass  or  tin  cooler  with  supply  and  over- 
flow pipe  for  water,  to  which  it  is  fastened  by  the  descending 
and  the  adapter  tube,  which  pass  through  the  cooler.  The  whole 
is  supported  by  a  tripod  bearing  the  cooler,  attached  to  which 
is  also  a  holder  for  the  lamp.  The  tripod  also  carries  below  a 
horizontal  shelf,  on  which  a  tube-stand  moves  in  a  slide,  there 
being  five  tubes  marked  each  for  100  cubic  centimetres ;  these 
are  intended  to  receive  the  various  quantities  of  oil,  which  dis- 
til over  at  or  between  certain  boiling  points.  The  retort  is  not 
to  be  charged  to  more  than  one-third  its  capacity ;  the  bulb  of 
the  thermometer  must  not  be  allowed  to  dip  into  the  oil,  but 
its  scale  below  the  mark  of  80°  C.  must  not  be  visible  above  the 
cork. 
This  contrivance  may  be  made  to  answer  some  purposes  in  a 
pharmaceutical  or  technical  laboratory  besides  the  one  for  which 
it  was  originally  intended. 
Sublimation  of  Alkaloids — Dr.  Helwig.  of  Mayence,  has 
published  (in  Fresenius'  Zeitschrift,  186-1,  p.  43)  researches  on 
microscopic  tests  applicable  for  diagnosis,  and  among  these  de- 
scribes the  sublimation  of  nearly  all  medicinal  alkaloids,  which 
he  states,  when  properly  treated,  furnished  perfect  objects  for 
micro-chemical  examination.  The  alkaloids  in  the  form  of  fine 
powder,  are  heated  very  carefully  on  a  piece  of  platinum  foil, 
hollowed  out  somewhat,  and  covered  with  a  plain  glass  plate. 
Most  of  the  sublimates  are  stated  to  be  crystalline ;  those  of 
morphia  and  strychnia  are  obtained  with  especial  facility,  and 
allow  the  application  of  all  the  usual  tests.  They  are  readily 
distinguished  by  a  dilute  solution  of  chromic  acid,  which  forms 
crystals  with  strychnia,  but  not  with  morphia.  Brucia  does 
not  yield  so  readily  a  crystalline  sublimate,  nor  is  the  reaction 
with  chromic  acid  as  distinct.  Veratria,  solania  and  aconitia 
also  give  crystalline  sublimates  ;  the  product  in  the  latter  case 
is  perfectly  soluble  in  ammonia,  from  which  solution  it  again 
crystallizes  on  evaporation.  Atropia  is  very  easily  destroyed 
when  too  high  a  degree  of  heat  is  employed  ;  when  carefully 
