[Oct.  I,  1895. 
27«  THE  TROPICAL 
AND  CARDENS  OF  THE  CANARY 
ISLANDS. 
A paper  read  before  the  Royal  Horticultural 
Society  May  It,  1895.  Ry  D.  Morris,  C.M.O., 
M.A.,  I)  sc^,  Assistant  Director,  Royal 
U.'U’ilcn.s,  Hon.  Treasurer,  Royal  Hor- 
tieultural  &ocietJ^  We  have  received  from  Mi*. 
-Morris  a copy  of  this  very  interesting  [laper, 
winch  will  be  fully  noticed  later  on  in  our 
Tropical  A gric id f urint. 
■ ♦ 
THE  METEOROLOGY  OF  CEYLON  FOR  1894  : 
ARE  WE  IN  THE  MIDST  OF  A DRY  CYCLE  ? 
This  Administration  Report  for  1894  on  the 
^Meteorology  of  Ceylon  is  by  Mr.  D.  G.  Mantell, 
Surveyor-General.  There  is  a considerable  degree 
of  monotony  in  reading  a report  of  this  nature, 
especially  in  the  tropics,  where  the  mercury  in 
tlie  barometer  appears  to  the  casual  observer  to 
be  .xs  fixed  and  immovable  as  tlie  w'all  on  which 
the  instrument  hangs.  The  thermometer,  too, 
seems  to  be  asleep  in  those  latitudes.  The  heat 
at  night  is  ne.arly  the  same  as  at  midday  in  the 
shade,  and  tlie  temiicraturc  of  August  differs 
little  from  that  of  December.  AVIi.at  is  the  mean- 
ing, wdicn  we  come  to  statistics,  of  tlie  remark 
we  sometimes  make  after  .a  shower— “ How  deli- 
ciously cool  it  is  now”?  Hriefly  this,  that  the 
temperature  has  dropjied  perliaiis  some  four  01  li\  o 
degrees  as  shown  by  the  Fahrenheit  scale.  M'bat, 
on  the  other  hand,  do  our  friends  at  home  mean 
when  they  tell  us  that  the  weather  has  suddenly 
become  cedder?  Probably  a droj)  of  twenty  or 
thirty  tlegrees,  or  more,  in  the  twenty-four  hours. 
Consecpieiitly  out  here  in  stewy  tropical  Colombo 
wlien  on  an  early  North-East  monsoon  morning, 
our  temperature  sinks  to  the  seventies  (say  7.) 
to  77°)  old  residents  facing  the  keen  air  are 
apt  to  s.ay,  “it  is  bitterly  cold.”  “ Ritterly 
cold”  with  very  much  the  temperature  maint.ained 
in  the  jialin-house,  KewGaidens  ! The  tides  .seem 
to  follow  tlie  same  rule  of  doing  as  little  work  as 
as  possible.  We  get  our  18  indies  bere  ; at  home 
we  m.ay  have  been  accustomed  to  get  18  feet! 
■\Ve  note  that  in  the  Meteorological  system  un- 
der the  Surveyor-General  there  are  10  jirincipal 
stations,  that  is,  stations  recording  daily  the 
readings  of  the  barometer,  the  “ wet  bulb  ” and 
“dry-bulb”  thermometers,  the  m.axinium  wet 
and' dry,  the  minimum  wet  and  dry,  the  solar 
railiation  thermometer,  terrestrial  radiation  ther- 
mometer, anemometer,  wind  vane,  and  rain- 
"auge.  In  addition  to  these,  there  are  7.3  stations 
re])orting  only  the  rainfall. 
Some  of  our  readers  may  not  be  aware  that 
the  beat  of  the  sun’s  rays  in  various  parts  of  the 
island  averages  generally  from  00  to  60  degrees 
above  the  mean  sh.ado  tcm])erature  of  the  loca- 
lity. -At  first  .sight,  and  in  view  of  the  remarks 
we  have  made  above  as  to  the  difference  between 
a cool  day  and  hot  day,  this  seems  oxces.sive. 
Ibit  it  is  not  so  bad  as  it  looks,  as  we  learn  from 
the  Report  under  review  that  the  solar  radiation 
thermometer  is  an  instinment  with  its  bulb 
blackened  with  lampblack  to  make  it  ab.sorb 
all  the  heat  it  c.an  get,  and  enclosed  in  a glass 
v.aeunm-iacket  to  preserve  it  from  air  currents 
and  ena)de  it  t(t  retain  its  heat.  Few  substances, 
we  supimse,  w’ould  acquire  by  exposure  to  the 
sun’s  rays  in  the  open  ,air  the  temperatures  in- 
dic.ated  by  the  sobar-r.adi.ation  thermometer  of  the 
meteorologist,  a form  of  in.strumcnt  which  is 
adopted  to  facilitate  the  comiiarison  of  readings 
taken  in  different  places. 
AGRICULTURIST. 
The  range  of  variation  of  shade  temperature 
is  very  interesting.  The  greatest  range  in  any 
one  month  was  at  Nu'var.a  Eliya,  and  amounted  to 
37°  8 in  December.  The  gre.a test  range  in  the  whole 
year  w:is  also  at  the  Sanatarium  and  amounted  to 
46°'7.  The  highest  shade  temperature  registered 
at  that  station  during  the  year  being  78°’0  on 
the  I7th  May,  and  the  lowe.st  31°'3on  the  27th 
December.  Next  to  this  comes  Puttalam  with 
a range  of  38°T;  while  Kandy  is  3o°.0,  Colombo 
25°‘8,  and  Galle  (the  lowest)  20°'0 
The  barometer  tables  are  most  uninteresting  to 
the  lay  reader.  The  l)arometcrs  do  very  little 
M’ork  app.arently.  The  Colony  supports  sixteen 
standard  instruments,  -worth,  xve  suppo.se,  several 
pounds  sterling  apiece  and  wdiat  do  they  do  for 
their  living  ? Sometimes  they  move  a thousandth 
]iart  of  an  inch,  sometimes  a hundredth,  in  .a 
day.  Of  the  whole  sixteen,  xvith  every  variety 
of  climate,  and  all  the  care  and  attention  that  a 
poorly-paid  stall  of  observers  can  afford  to  bestow, 
not  one  could  show  a variation  of  half  an  inch 
in  the  whole  year  ! The  British  householder  who 
taps  the  “ weather  glass”  in  his  front  hall  every 
day  of  the  year  as  regularly  as  clock-work  and 
as  regularly  infers  from  his  observation  tii.at  it 
will  l)c  prudent  to  take  bis  umbrelba,  would  be 
quite  non-plus.sed  iji  Colombo.  If  the  band  pointed 
to  “ Set  Fair”  todajg  it  would  point  to  “ Set 
Fair  ” every  day  “ till  furtber  notice”  or  until 
the  nail  it  hung  on  luid  rusted  .away  ! 
When  the  atmosphere  is  hot,  it  c.an  hold  in 
suspension  more  moisture  than  when  it  is  cold. 
For  every  degree  of  temperature,  therefore,  there 
is  a certain  quantity  of  moisture  which  can  stay 
in  suspension,  .and  no  more.  If  the  .air  gets  more 
moisture  than  th.at  quantity,  or  if  the  tempera- 
ture of  the  air  falls,  the  moisture  is  condensed 
and  falls  in  the  form  of  rain,  snow,  or  h.ail  ac- 
cording to  the  climate.  The  dewon  the  outside 
of  a tninbler  of  icetl  water  is  produced  in  this 
way.  M'hen  the  atmosphere  contains  all  the  mois- 
ture it  c.an  keep,  it  is  s.aid  to  be  “ saturated.” 
Meteorologists  express  the  degrees  of  liumidity  by 
calling  the  satnration-j)oint  lOU  .and  absolute  dry- 
nc.ss,  zero.  \Vben  they  state  that  the  humidity 
is  50,_  they  mean  to  signify  that  the  atmosphere 
conLains  half  as  much  moisture  as  it. would  hohl  .at 
satur.ation  point  .at  the  same  temperatui-e.  The 
Report  under  review  shows  that  the  humidity 
was  lower  in  1894  than  in  the  average  ye.ar,  at 
nearly  every  station,  by  an  .amount  varying  from 
1 to  5 of  the  degrees  just  mentioned.  It  naturally 
follows  from  a low  humidity  that  there  must  be 
less  rainfall.  This  we  find  to  have  been  the  Ciise  in 
1894.  Ne.arly  every  station  w.as  short  of  r.ain  to 
an  amount  varying  u))  to  27  inches.  The  s.ame 
experience  is  likely  to  be  noted  for  1893,  .so  that 
it  would  really  seem  as  if  wc  M'ere  in  the  midst 
of  one  of  Tytler’s  “Dry  Cycle.s.”. 
« 
ExPOKTS  op  COFPKK  and  Pp.PPKH  PIHIM 
SoUTiipuN  India.— We  call  attention  to  the 
interesting  letter  and  return  sent  us  by  our  old 
friend,  Mr.  R.al|)h  Tatb.am,  on  behalf  of  Messrs. 
Arbutbnott  A Co.  Two  new  ]iorts  having  been 
included,  a fair  comparison  with  previous  years 
cannot,  perhaps,  be  ollered  ; but  we  may  men- 
tion that  while  291,021  cwt.  Cofl'ee  were  sent 
aw.ay  in  1.894-93  ; the  <|uanlity  recorded  in  the 
previous  three  years  (for  the  same  periods,  but  less 
two  ]H)rts)  were  239  900;  221 ,3.33  and  308,2.8:1  ewt. 
rcsp(!ctively.  As  to  Pepper,  the  lignres  for  four  sea- 
sons com]>,are  thus  under  the  same  con -conditions  : — ■ 
(bvt.  Cwt. 
1894-3  = 132,4.39  1.892-3=  l.37,.3.33 
1893-4  = 172,803  1891-2  = 1:33,941 
