Recent  British  Weather. 
413 
Tables  of  temperature  relating  to  Camden  Square,  in  the  north 
of  London,  and  to  Greenwich,  lend  themselves  more  readily 
to  my  present  object  than  any  others  ; but  as  it  may  be  alleged 
that  observations  from  the  outskirts  of  a great  city  are  scarcely 
suitable  for  agricultural  purposes,  I will  begin  by  a brief  com- 
parison of  some  of  the  principal  facts  relating  to  1882  at  the 
two  metropolitan  and  at  two  widely-distant  country  stations — 
both  nearly  in  the  same  latitude. 
Table  I. — Temperatures  in  1882. 
Stations. 
Absolute. 
Average. 
Mean. 
Max. 
Min. 
Max. 
Min. 
Strathfield  Turgiss,  Hants 
Eoss,  Hereford 
o 
83- 7 
84- 1 
o 
18-0 
19-6 
o 
57-9 
57-1 
o 
41- 3 
42- 3 
49°  6 
49-7 
Greenwich  Eoyal  Observatory 
London,  Camden  Square  .. 
81-0 
80-8 
22-2 
24-5 
57- 8 
58- 2 
42- 6 
43- 1 
49-7 
503 
This  indicates  that  the  metropolitan  stations  are  on  the 
average  a few  tenths  warmer  than  other  places  in  the  same 
latitude,  but  that  for  all  practical  purposes  the  town  and  country 
stations  agree.  Curiously  enough,  in  1882,  the  maximum  tem- 
peratures at  the  metropolitan  stations  are  below  those  at  the 
country  ones  ; this  is  unusual,  for  the  records  from  Greenwich 
have  often  exceeded  those  at  any  other  station  in  the  country. 
Having  now  got  the  coast  cleared  from  preliminary  difficulties, 
I may  begin  to  attack  the  question  of  whether  recent  years 
show  exceptional  departures  from  the  average  of  long  series  of 
previous  years. 
In  the  first  place,  I have  compiled  from  various  publications 
by  Mr.  J.  Glaisher,  F.R.S.,  the  following  table  of  the  mean 
temperature  of  each  of  the  last  112  years,  as  observed  at  Green- 
wich since  1841,  and  as  computed  for  previous  years  from 
observations  made  in  the  Metropolis.  (Table  II.,  p.  414.) 
The  first  feature  which  that  table  renders  evident  is  the  con- 
siderable difference  between  the  average  of  the  first  50  years 
(47°-9)  and  the  last  50  years  (49° -3),  a rise  of  very  nearly  1 J 
degrees.  Mr.  Glaisher  believes  that  this  is  a real  rise.  As,  how- 
ever, the  fact  has  been  doubted,  and  the  whole  question  of  secular 
change  of  temperature  is  now  being  investigated,  and  as  we  are 
concerned  rather  with  the  temperatures  of  the  last  quarter  of  a 
century  than  with  that  of  remote  periods,  we  may  confine  our 
attention  to  the  43  years  from  1840  onwards.  The  average  of 
this  period  is  about  490,3,  and  an  examination  of  Table  II.  will 
