BENZOL  SERIES  IN  CANADIAN  PETROLEUM. 
311 
become  a  valuable  addition  to  its  commerce,  as  well  as  adding 
to  the  supply,  which,  at  the  present  increasing  rate  of  consump- 
tion, is  much  to  be  desired,  may  be  crowned  with  success. — Lon. 
Pharm.  Joum%,  June,  1865,  from  The  Technologist. 
WHAT  IS  AN  INCH  OF  RAIN. 
The  last  weekly  return  of  the  Registrar-General  gives  the 
following  interesting  information  in  respect  to  rain-fall : — "  Rain 
fell  in  London  to  the  amount  of  0-43  inch,  which  is  equivalent 
to  43  tons  of  rain  per  acre.  The  rain-fall  during  last  week 
varied  from  30  tons  per  acre  in  Edinburg  to  215  tons  per  acre 
in  Glasgow.  An  English  acre  consists  of  6,272,640  square 
inches;  and  an  inch  deep  of  rain  on  an  acre  yields  6,272,640 
cubic  inches  of  water,  which  at  277*274  cubic  inches  to  the  gal- 
lon makes  22,622-5  gallons  ;  and,  as  a  gallon  of  distilled  water 
weighs  10  lbs,  the  rain-fall  on  an  acre  is  226,225  fos  avoir- 
dupois ;  but  2240  lbs  are  a  ton,  and  consequently  an  inch  deep 
of  rain  weighs  100*993  tons,  or  nearly  101  tons  per  acre.  For 
every  100th  of  an  inch  a  ton  of  water  falls  per  acre."  If  any 
agriculturist  were  to  try  the  experiment  of  distributing  arti- 
ficially that  which  nature  so  bountifully  supplies,  he  would  soon 
feel  inclined  to  "  rest  and  be  thankful." — Jour.  Franklin  In- 
stitute, from  the  Jour,  of  the  Society  of  Arts,  No.  639. 
PRESENCE  OF  THE  BENZOL  SERIES  IN  CANADIAN 
PETROLEUM. 
By  C.  Scholemmer,  Esq. 
Pelouze  and  Cahours  state  that  American  petroleum  which 
they  used  did  not  contain  hydrocarbons  of  the  benzol  series, 
whilst  I  found  a  not  inconsiderable  quantity  of  these  compounds 
in  the  rectified  petroleum  from  which  I  isolated  the  hydrides  of 
heptyl,  &c.  As  it  was  not  impossible  that  this  was  an  accidental 
or  intentional  admixture,  I  endeavored  to  procure  some  genuine 
crude  American  petroleum,  but  I  did  not  succeed  in  obtaining 
crude  genuine  Pennsylvanian,  as  none  of  it  had  reached  the  Liv- 
erpool markets  for  months.    I,  however,  got  some  real  Canadian 
