80 
5  VARIETIES. 
some  actual  change  in  their  chemical  characters  and  therapeutical  proper- 
ties. At  present  he  can  adduce  two  or  three  decided  examples,  which  lead 
him  to  form  this  opinion ;  these  are — common  sugar,  gum  arabic,  and 
arsenic,  or  arsenious  acid.  We  all  know  that  sugar,  when  pulverized,  be- 
comes less  soluble  in  water,  and  less  sweet  to  the  taste.  He  asks,  Is  this  to 
be  referred  to  an  altered  electrical  condition  of  the  sugar,  as  the  phosphor- 
escence developed  during  the  act  of  pulverization  in  the  dark  would  lead  us 
to  suspect  ?  The  next  article  mentioned,  gum  Arabic,  when  powdered,  has 
neither  the  same  taste  nor  the  same  degree  of  solubility  as  when  in  the  en- 
tire state  ;  and  he  states  that  the  effect  of  pulverization  upon  white  arsenic, 
or  arsenious  acid,  is  so  great,  as  regards  its  solubility  in  water,  that  whilst 
a  given  quantity  of  water  may  be  made  to  dissolve  forty  parts  in  the  vitreous 
state,  the  same  quantity  of  water  can  be  made  to  dissolve  only  fourteen 
parts  after  pulverization. — Annals  of  Pharmacy,  May,  1852. 
Electricity. — Professor  Faraday  has  instituted  a  series  of  experiments, 
with  a  view  to  determine  the  quantity  of  electricity  connected  with  the 
atoms  or  particles  of  matter.  He  says,  it  is  wonderful  to  observe  how  small 
a  quantity  of  a  compound  body  is  capable  of  being  decomposed  by  a  certain 
quantity  of  electricity.  "  One  grain  of  water  will  require  for  decomposition, 
an  electric  current  equal  to  a  very  powerful  flash  of  lightning."  The 
chemical  action  of  a  grain  of  water  upon  four  grains  of  zinc,  can  evolve 
electricity  equal  in  quantity  to  that  of  a  powerful  thunderstorm  ;  and  he 
states,  that  from  his  experiments  it  would  appear,  that  800,000  such  charges 
of  the  Leyden  battery  would  be  necessary  to  supply  electricity  sufficient  to 
decompose  a  single  grain  of  water.  The  Leyden  battery  of  which  he  speaks 
consists  of  fifteen  jars,  containing  3510  square  inches,  or  about  twenty- 
four  and  a  half  square  feet  of  coated  glass,  charged  by  thirty  turns  of 
a  plate  electrical  machine,  the  plate  being  fifty  inches  in  diameter,  and  of 
immense  power,  giving  ten  or  twelve  sparks  an  inch  long  for  each  revolu- 
tion. The  author  of  a  paper  on  this  subject  in  the  Philosophical  Magazine, 
remarks,  that  "  the  estimate  that  800,000  discharges  of  the  battery  of  fif- 
teen jars,  equal  to  a  powerful  flash  of  lightning,  would  be  necessary  to 
resolve  a  single  grain  of  water  into  its  elements,  is  certainly  astounding, 
when  it  is  recollected  that,,  according  to  Professor  Faraday,  the  quantity  of 
electricity  that  decomposes  a  body,  is  the  equivalent  quantity  of  electricity 
that  had  previously  held  the  elements  of  that  body  in  combination  ;  for  he, 
with  Davy  and  others,  conceives  that  electricity  and  chemical  affinity  are 
identical  powers.  Hence  in  one  grain,  that  is,  one  drop  of  water,  there 
must  be  naturally  existing,  and  constituting  the  affinity  between  its  oxygen 
and  hydrogen,  no  less  a  quantity  of  electricity,,  than  800,000  charges  of  a 
battery  containing  3510  square  inches  of  coated  glass,  or  the  equivalent  of 
a  very  powerful  flash  of  tlightning.  If  this  quantity  of  electricity  were 
converted  into  one  spark,  it  would  be  4166  miles  in  length,  taking  Professor 
