Am'junUeI!"i903arm'}     Simple  Forms  of  Laboratory  Apparatus.  257 
Mixed  Alkaloids 
by  Titration. 
Strychnine. 
Proportion  of 
Strychnine  in 
Total  Alkaloids. 
Per  cent. 
Per  cent. 
Per  cent. 
19-9 
7-96 
40 
664 
44 
2-9 
1-27 
44 
Fluid  extract  nux  vomica  seeds  
1*96 
o-88  . 
45 
SIMPLE  FORMS  OF  LABORATORY  APPARATUS. 
By  Frank  X.  Moerk. 
Of  the  laboratory  apparatus  used  in  chemical  analysis,  none  is  of 
greater  importance  than  the  hydrogen  sulphide  generator.  The 
apparatus  described  in  this  paper  is  inexpensive  in  construction  and 
use  and  will  remain  in  action  until  the  sulphuric  acid  is  nearly  neu- 
tralized. 
A  is  a  gallon  wide-mouth  bottle  nearly  filled  with  dilute  sulphuric 
acid,  10  per  cent.;  into  this  hangs  a  student  lamp  chimney  B  sup- 
ported in  the  neck  of  the  bottle  by  means  of  a  paraffined  wooden 
block  ;  B  contains  a  notched  leaden  disk  ft  which  supports  the  fer- 
rous sulphide  to  be  acted  upon  and  is  closed  by  perforated  rubber 
corks,  the  upper  one  supporting  a  delivery  tube  made  up  of  a  glass 
tube  bent  at  right-angles  and  a  short  piece  of  rubber  tubing  con- 
taining the  tightly  fitting  glass  plug  a ;  the  lower  one  supporting 
two  valves  b  and  made  of  two  sizes  of  glass  tubing  and  perforated 
rubber  corks,  the  lower  one  e  in  each  valve  being  notched,  the 
upper  one  perfectly  smooth,  so  that  an  ordinary  cork  d  may  either 
close  the  valve  by  being  forced  against  the  upper  cork  or  open  the 
valve  by  being  forced  downward. 
The  apparatus,  having  been  charged,  works  as  follows  :  By  press- 
ing the  rubber  tubing  at  a  to  form  a  small  channel  alongside  of  the 
glass  plug,  the  acid  is  allowed  to  enter  the  lamp  chimney  through 
the  valve  c  and  generate  the  gas,  the  valve  d  remaining  closed ; 
upon  releasing  the  pressure  at  a,  the  generation  of  gas  continues 
until  the  pressure  of  the  accumulated  gas  forces  the  acid  out  of  the 
chimney  through  the  valve  d,  the  upper  valve  remaining  closed. 
Each  time  the  generator  is  used  fresh  or  the  least  saturated  acid 
enters,  this  on  being  discharged  sinking  to  the  bottom  of  the  bottle, 
