VARIETIES. 
91 
duction  of  mechanical  power  alone,  from  which  a  power  equal  to  that  of 
56,000,000  able  bodied  men  is  obtained.  Each  acre  of  a  seam  yielding 
three  feet  of  pure  fuel,  is  equal  to  about  5000  tons,  and  possesses  a  reserve 
of  mechanical  strength  equal  to  the  labor  of  1600  men  during  their  whole 
life  ;  and  each  square  mile  of  the  same  bed  contains  8,000,000  tons  of  fuel 
which  is  equal  to  1,000,000  men  laboring  through  twenty  years  of  their 
ripe  strength.  Upon  the  same  calculation,  the  total  annual  coal  production 
of  the  United  Kingdom  (65,000,009  tons)  is  equal  to  the  strength  of  400,- 
000,000,  strong  men,  or  more  than  double  the  number  of  adult  males  now 
upon  the  globe. — Lond.  Mech.  Mag.,  Sept.  1861. 
India- Bubber  Stoppers  for  Bottles.  Messrs.  Editors, — Will  you  allow  me 
to  call  the  attention  of  the  profession,  through  your  pages,  to  a  recent  in- 
vention which  promises  to  be  of  great  convenience  to  physicians,  as  well  as 
to  all  other  classes  of  the  community.  I  refer  to  the  India-rubber  corks  for 
bottles  and  vials.  By  means  of  this  admirable  substitute  for  the  common 
cork,  bottles  containing  the  strongest  acids  may  be  carried  without  danger 
in  the  pocket,  and  the  great  inconvenience  and  expense  of  ground-glass 
stoppers  obviated.  The  vulcanized  rubber  of  which  they  are  made  will 
resist,  I  believe,  all  chemical  agents.  I  have  kept  a  bottle  of  concentrated 
sulphuric  ether,  closed  with  one  of  these  stoppers  inverted  for  several  days, 
without  the  slightest  visible  effect  being  produced  on  the  gum. 
For  alcohol,  solutions  of  nitrate  of  silver,  tincture  of  iodine,  the  various 
mineral  acids,  and  indeed,  for  all  liquids,  the  India-rubber  stopper  is  more 
than  a  convenience,  it  is  a  positive  luxury,  as,  I  am  confident,  all  will  agree 
who  have  tried  it.  To  practitioners  in  the  country,  who  carry  their  own 
medicines  with  them,  it  will  be  of  inestimable  advantage.  In  the  sick  room, 
also,  the  new  stopper  is  of  very  great  utility.  By  means  of  it,  bottles  con- 
taining effervescing  fluids,  such  as  champagne,  citrate  of  magnesia,  soda- 
water,  &c,  can  be  tightly  corked  again  after  having  been  opened,  so  that 
small  quantities  of  their  contents  may  be  used  at  a  time  without  the  slight- 
est detriment  to  the  remainder.  Lastly,  and  not  least,  these  corks  are  sold 
at  a  price  which  will  place  them  within  the  reach  of  all.  M. — Boston 
Med.  and  Surg.  Journ.,  Dec.  12,  1861. 
Reputed  Specific  for  Small-pox — At  the  last  nieetingof  the  Epidemiological 
Society,  a  communication  was  read  from  Mr.  Herbert  Miles,  Assistant  Sur- 
geon to  the  Royal  Artillery,  respecting  a  plant  that  was  stated  to  be  a 
specific  for  small-pox.  The  remedy  is  given  in  the  form  of  a  strong  infu- 
siou  of  the  rhizome,  and  Mr.  Miles  had,  after  very  considerable  difficulty, 
succeeded  in  obtaining  a  small  supply  of  the  plant,  which  he  had  forward- 
ed to  the  Society. 
Mr.  Miles  is  quartered  in  Canada,  where  an  epedemic  of  small-pox  having 
broken  out  among  the  Indians,  the  disease  had  proved  virulent  in  the  ex- 
