174  Practical  Notes  from  Various  Sources.  {A,VPH\?i8ooarm' 
Plaster  of  Zinc  oxide,  (20  per  cent.) — Dammar,  15  ;  tallow,  25; 
lanolin,  15;  caoutchouc,  5;  glycerin,  20;  zinc  oxide,  20  parts. 
Melt  the  resin,  add  the  tallow  and  strain  through  gauze ;  then  add 
the  lanolin  and  the  caoutchouc  solution,  cautiously  evaporate  the 
benzol  and  add  the  zinc  oxide  previously  rubbed  up  with  the 
glycerin  ;  lastly  stir  until  a  homogeneous  mixture  is  obtained.  On 
spreading  it  upon  muslin,  the  mass  should  not  be  too  warm.  One 
kilo  of  mass  will  suffice  for  25  to  30  meters  of  plaster  20  cm.  in 
width,  and  this  may  be  spread  in  1  or  \y2  hours.  The  plaster  is 
finally  exposed  to  the  air  for  2  or  3  days,  covered  with  gauze  and 
preserved  in  paper. 
Plaster  of  Iodoform. — Dammar,  1 5  ;  tallow,  30  ■  lanolin,  20  ; 
caoutchouc,  5  ;  glycerin,  10  ;  iodoform,  20  parts.  Proceed  as  before, 
and  add  the  iodoform,  well  triturated  with  the  glycerin,  to  the  nearly 
cooled  mass.    Keep  the  plaster  in  a  tin  box. 
Plaster  of  Mercury. — Dammar,  20 ;  tallow,  34  ;  lanolin,  20 ) 
caoutchouc,  6;  mercury,  20  parts.  Rub  the  mercury  with  the 
lanolin  until  no  globules  remain  visible  and  add  this  to  the  nearly 
cool  mixture  of  the  other  ingredients,  prepared  as  stated  above. 
CHEMICAL  NOTES. 
By  Henry  C.  C.  Maisch,  Ph.G.,  Ph.D. 
Sugar  reagent. — Matthieu-Plessy  (Monit.  Scientif,  1889,  1446) 
gives  the  following  reagent  for  cane-sugar,  grape-sugar,  and  pyro- 
gallic  acid :  54  pts.  of  ammonium  nitrate  are  fused,  and  34  pts.  lead 
nitrate  and  21  pts.  of  plumbic  hydrate  are  added.  The  reagent 
melts  at  ^05°  C,  and  with  the  substances  named  gives  mix- 
tures, having  in  the  presence  of  glucose  a  cherry  red,  with  cane-sugar 
a  coffee  colored,  and  with  pyrogallic  acid  a  chrome-green  color. 
Mnsscenda  coffee. — Prof.  Dunstan  (Pharm.  Journ  and  Trans.,  Nov! 
16,  1889,  381)  analyzed  the  above  and  could  not  find  a  trace  of  the 
0-3-0-5  per  cent,  coffeine  which  was  said  to  be  contained  in  these 
seeds,  supposed  by  Lapeyrere  (1888)  to  be  derived  from  Musscenda 
borbonica,  a  new  species  of  Rubiacese.  Dunstan  found  no  alkaloid 
(doubtful  traces  of  choline  excepted);  but  ascertained  the  presence 
of  much  protein,  little  sugar,  and  of  a  fat  resembling  that  of  nux 
vomica.  According  to  investigations  carried  on  in  the  Kew  Gardens, 
the  seeds,  which  Lapeyrere  commended  as  a  substitute  for  coffee, 
come  from  Gcertnera  vaginata,  a  loganiaceous  shrub. 
