^\^^ri^mT'}       On  Breakage  of  Glass  Vessels.  "  197 
to  avoid  all  loss  of  glassware  from  sudden  change  of  temperature. 
During  that  time  I  have  always  been  in  the  habit  of  making  the 
solution  of  citrate  of  magnesia  with  hot  water,  and  filtering  it  at  once 
into  glass  vessels.  I  have  always  strained  hot  syrups  into  glass 
bottles,  and  have  been  in  the  habit  of  measuring  hot  liquids  in  ordi- 
nary glass  graduate  measures.  Fruit  syrups  made  in  the  summer 
season,  I  have  always  bottled  while  hot  in  ordinary  bottles,  and 
hot  liquids  of  every  kind  I  have  handled  in  the  same  manner.  In  all 
this  time  I  have  never  broken  or  had  broken  in  my  store  a  single 
bottle  or  vessel  from  sudden  change  of  temperature. 
One  day  a  man  who,  from  his  conversation,  I  supposed  to  be  an 
old  sailor,  stopped  in  the  store.  After  making  some  slight  purchase, 
he  opened  a  wandering  conversation  with  me  on  various  subjects,  and 
finally,  after  talking  about  spiritualism,  magic,  etc.,  he  began  to  speak 
on  matters  which,  if  not  scientific,  are  at  least  curious.  Among  other 
matters  he  mentioned  the  fact  that,  in  making  hot  punch,  he  had  ob- 
served that  if  the  hot  liquid  be  poured  into  a  cold  glass, 
under  ordinary  circumstances,  the  glass  will  generally  break  ;  but  if  a 
spoon  be  placed  in  the  glass,  there  will  be  no  breakage.  I  had 
nothing  to  say  at  the  time,  but  it  struck  me  that  there  was  a  thought 
which  might  be  of  service  to  the  profession.  I  have  since  ascertained 
that  my  maritime  friend  is  not  the  only  one  acquainted  with  the 
punch  making  process.  It  has  been  known  to  certain  persons  for 
many  years — was  known  seventy  years  ago  to  my  grandfather.  It 
occurred  to  me  that  there  is  nothing  in  the  peculiar  form  of  the  spoon 
and  glass  to  prevent  the  breakage,  and  that,  if  the  statement  be  true 
of  the  spoon  and  tumbler,  the  principle  will  also  apply  to  a  rod  and 
bottle.  I  tried  a  few  simple  experiments,  which  satisfied  me  that  the 
principle  is  of  use,  and  have  employed  it  in  practice  ever  since.  I 
have  on  hand  a  number  of  metallic  rods,  and  when  I  have  occasion  to 
pour  a  hot  liquid  into  a  cold  bottle,  jar  or  measure,  I  simply  place  a 
metallic  rod  in  the  vessel,  and  slowly  pour  the  hot  liquid  down  the 
rod.  With  proper  manipulation  and  the  adoption  of  this  process,  I 
am  satisfied  that  no  apothecary  need  ever  lose  a  single  bottle  by 
breakage  caused  by  change  of  temperature. 
The  rule  may  be  applied  both  ways.  After  a  hot  liquid  has  been 
placed  in  a  vessel  protected  by  the  rod,  the  liquid  may  be  poured  out, 
the  rod  replaced,  the  vessel  washed  at  once  with  cold  water  and  used 
for  any  other  purpose.    Fluid  extracts  while  evaporating  may  be  at 
