Am.  Jour.  Pharm. 
June,  1898. 
Hydrogen  Peroxide. 
291 
(7)  Longitudinal  section  through  the  pulp  of  banana  fruit  near  a  fibro-vascu- 
lar  bundle,  showing  large  membered  mucilage  secretion  cell. 
(8)  Transverse  section  through  a  commercial  specimen  of  Althaea  root  treated 
as  described  in  the  test,  showing  large  mucilage  cells  with  lamellae  and  irregu- 
lar protoplasmic  contents. 
(9)  Transverse  section  through  a  commercial  specimen  of  Ulmus  treated  simi- 
larly to  the  Althaea  specimen.  The  large  mucilage  cells  are  surrounded  by 
parenchyma  cells  containing  starch  and  calcium  oxalate  crystals  and  a  few  bast 
fibres. 
(10)  Transverse  section  of  seed  coat  of  Sinapis  alba,  showing  outer  mucilagin- 
ous wall. 
(11)  Transverse  section  of  seed  coat  of  linum  showing  outer  mucilaginous 
wall. 
(12)  Nearly  mature  secretion  hair  on  leaf  of  Viola  tricolor,  L.  The  cells  upon 
the  peripher}'  contain  a  large  nucleus,  protoplasm  and  a  few  relatively  large 
vacuoles. 
(13)  Fully  matured  secretion  hair  on  leaf  of  Viola  tricolor,       with  stalk. 
(14)  Mature  secretion  hair  of  Viola  tricolor,  L. ,  that  was  ready  to  discharge  its 
mucilage.  Upon  mounting  in  a  glycerin  methylene  blue  solution  or  in  picro- 
nigrosin  and  pressing  upon  the  cover-glass  with  a  needle  or  pencil,  the  mucilage 
is  discharged  and  takes  up  the  stain. 
1/ 
HYDROGEN  PEROXIDE  AS  A  FACTOR  IN  SPONTA- 
NEOUS COMBUSTION. 
By  Charges  H.  LaWaij,.' 
The  danger  of  explosion  of  hydrogen  peroxide,  when  kept  in 
tightly  stoppered  bottles,  has  long  been  recognized  as  a  serious 
drawback  to  the  purchase  of  any  considerable  quantity  at  one  time. 
The  deterioration  or  decomposition  which,  in  the  most  favorable  in- 
stances, takes  place  to  some  extent  after  several  weeks'  standing  in 
the  bottled  condition,  is  accompanied  by  liberation  of  oxygen,  which 
(if  the  bottle  be  very  tightly  stoppered)  accumulates  until  the  pres- 
sure is  great  enough  to  force  out  the  stopper  or  burst  the  bottle, 
the  latter  circumstance  occasionally  being  attended  by  considerable 
damage  to  objects  in  the  immediate  vicinity. 
Although  a  working  process  was  included  for  the  preparation  of 
hydrogen  peroxide  in  the  1890  Pharmacopoeia,  at  the  time  of  its 
admission,  few  pharmacists  attempt  to  make  it  themselves,  and  its 
manufacture  is  confined  to  a  limited  number  of  firms  who  make  it  on 
a  very  large  scale. 
As  transportation  is  very  detrimental  to  it,  and,  considering  the 
large  amount  of  it  that  is  handled  yearly,  the  small  number  of  ex- 
