JrNK  I,  1896.] 
Svp})l(nnp}it  to  the  “ 7 roj)ical  A(jricHUurist'’ 
867 
of  two  parts  loam  one  of  leaf  moiiM,  with  a little 
charcoal  and  woodashes.  The  compost  which  is 
used  later  o;i  to  iiuluce  fruiting  should  be  ])re- 
j>ared  early  and  allowed  time  to  mellow  for  use 
when  required.  lu  addition  to  occasional  top- 
dressings  a handful  of  blood  manure  is  recom- 
mended for  each  plant. 
THE  UAlUl. 
Cleanliness  in  the  dairy  must  be  understood 
to  include  other  considerations  than  the  excliusion 
of  injurious  microscopic  bodies,  and  an  ins 
tance  C'f  this  truism  appears  in  the  following 
account  of  a comparatively  recent  experiment 
made  in  Denmark  by  M.  Doggild,  the  “ expert '' 
of  the  Eoyal  Danish  Agricultural  Society.  A 
.samjale  of  milk  from  a creamery  was  sent  to 
JI.  Boggild  tor  analysis.  Even  before  the  milk 
had  turned  sour  it  had  acquired  a very  bad  smell, 
and  a taste  somewhat  analogous  to  that  of  tallow. 
The  farm  whence  the  milk  originated  was  found  to 
be  not  only  well  conducted,  but  one  which  had  a 
very  good  reputation  in  its  district. 
Xevertheless,  M.  Boggild  observed  that  a tank 
employed  to  receive  the  milk  was  rusty,  and,  as  he 
remembered  having  once  before  met  with  an 
analogous  tibiiormity  in  milk  from  a farm  where 
he  had  also  observed  a similar  rusty  recejatacle,  M. 
Boggild  suggested  to  the  farmer,  as  an  experitnent, 
to  purchase  another  tank  to  be  used  side  by  side 
with  the  rusty  one.  The  experiment  was  made, 
and  whereas  the  milk  became  tainted  as  before  in 
the  old  case,  the  milk  [ilacod  in  the  new  tank 
retained  its  normal  qualities. 
This  result  appeared  convincing  enough,  but  1\1. 
Boggild  made  it  conclusive  by  further  investiga- 
tion with  a view  to  ascertain  whether  it  was  rust 
itself  that  caused  the  mi.schief,  or  whether  it 
might  be  due  to  bacteria,  which,  tliroiigh  inadequate 
cleansing,  might  also  be  laresent  in  the  rusty  vat. 
To  this  end,  therefore,  it  was  not  only  thoroughly 
washed,  but  also  steamed,  so  as  to  kill  any  con- 
taineiimicro-organisms.  But  even  this  precaution 
did  not  protect  the  milk,  which  was  afterwards 
placed  in  the  still  rusty  vat.  Jl.  Boggild  also 
found  it  on  analysis  to  contain  a comparatively 
larger  quantity  of  iron,  which,  moreover,  increased 
in  proportion  to  the  extent  of  rusty  surface 
covered  by  milk. 
It  was  also  shown  that  the  l.mtter  made  from 
this  milk  acquired  its  characteristic  taste.  This 
observation  serves  as  an  additional  proof  of  the 
necessity  to  use  only  il  day  ut-  n^ils  w inch  are  clean 
in  the  strict  sense  of  the  woi’d. 
Warts,  we  rend  i i the  Cable,  are  contagious,  and 
a milker  with  a warty  hand  may  very  likely 
cause  them  to  come  on  the  cow’s  teats.  The 
remedy  for  man  and  animals  is  to  apply  any 
caustic  preparation  to  the  wart  until  it  is 
corroded  away  and  a raw  spot  is  made  in  its  place. 
Then  apply  calomel  to  the  raw  surface  ami  pro- 
tect it  with  a bandage  until  healing  is  completed. 
When  a milking  caw  is  troubled  with  warts  on 
the  teats,  and  there  is  difficulty  in  milking,  a 
silver  tube  should  be  used  to  draw  out  the  milk, 
which  will  How  when  the  other  teats  are  milked. 
We  read  of  the  tollowing  being  given  to  cows 
in  Oudh  to  bring  them  into  season  ; Wheat,  1 seer ; 
llyocyanuis.niger,  1 oz.  ; licpiid  curd,  2 seers.  These 
are  mixed  togethe.r  in  an  earthen  pot  which  i.s 
closed  and  buried  in  an  old  dung  heap  for  a 
week.  IVhen  W('ll  fermented  it  is  dug  out  and  the 
mixturo  given  to  cows  in  two  or  three  instalments. 
M Arnault,  the  director  of  one  of  the  largest 
dairies  in  Baris,  lirmly  believes  that  food  does  tell 
on  the  yield  and  richne.ss  of  milk.  German 
authorities  are  of  opinion  that  food  has  no  in- 
lluence  in  determining  the  amount  of  butter  in  the 
solids  of  milk:  that  attribute,  they  state,  depends 
entirely  on  the  temperament  of  the  cow  alone. 
Milk  contains  from  10  to  14  per  cent,  of  solid 
matter,  consisting  of  to  6-i»0  of  butter  fat, 
which  is  insoluble,  and  the  re.st  of  a matter  which 
is  not  fat  but  is  soluble. 
THE  NUTRITIA'E  BROCE8.8  L\  PL.iNT8. 
Prof.  J.  Green,  D.Sc.,  F.ll.S. 
{Coni inued. ) 
But  the  mere  fortuitous  or  jare-arranged  meeting 
of  the  raw  material  is  not  sufficient.  AVhence 
comes  the  power  to  make  any  change  in  any  or  all 
of  them  r It  must  be  evident  on  a little  reflec- 
tion that  considerable  work  must  be  expended 
on  such  bodies  to  produce  more  comple.x  ones 
from  them. 
We  find  that  the  increase  in  weight  of  the 
plant  which  must  follow  the  building  up  of 
complex  bodies,  or  the  construction  of°its  own 
substance  from  these  .simple  ones,  can  only  take 
place  under  certain  external  conditions,  and  of 
these  the  mo.-t  important  is  exiaosure  to  sunlio-bt. 
Ex])osure  to  sunlight,  again,  is  quite  inoperative, 
unless  the  tissua  so  expose  1 contains  the  chlorn- 
plastids  already  described.  Evidently  some  re- 
la!  ion  exists  between  the.se  tvvo  factors. 
The  chlorophyll  can  be  extracted  from  the  plas- 
tid  which  contains  it,  by  the  simple  jaroce.ss  of 
soaking  Uie  leaf  in  alcohol.  When  such  a solution 
is  made  it  has  the  same  bright  green  appearance 
as  the  leaf  itself,  and  its  relation  to  sunlight 
can  be  examined.  If  a beam  of  light  be  made 
to  passthrough  a prism  of  glass,  it  does  not,  as 
is  well  known,  emerge  as  a simple  beam,  but 
the  different  rays  of  which  it  is  compared  are 
all  bent  from  the  straight  line.  Being  of  dif- 
ferent degn-ees  of  refrangibility— that  i,?,  being 
deflected  in  rliffeieut  ext-_*nr.s — the  rays  emer^^e 
from  the  prism  separately,  aiid,  imstead  of'’a 
.spot  of  white  light,  a baud  of  all  the  colours  of 
the  rainbow,  arranged  in  delinite  sequence,  falls 
on  any  surface  placed  in  the  path  of  the  beam 
after  emergence.  The  band  is  known  as  the 
solar  spectrum.  If  now  various  substances  be 
pi  iced  in  the  path  of  the  light  before  it 
reaches  the  prism,  it  is  found  that  this  band 
of  colours  is  often  very  much  affected,  not  being 
continuous,  but  crossed  by  vertical  black  or  dim 
bands,  indicating  that  certain  rays  have  been 
sifted  out  or  absorbed,  as  the  light  h.as  passed 
through  the  solution  of  the  substance  under 
experiment.  Chlorophyll  is  one  of  these  sub- 
stances ; if  a solution  of  it  be  tested  as  de.scribed 
the  resulting  spectrum  is  found  to  be  marked  bj’ 
seven  distinct  vertical  patches  which  are  called 
its  absorption  bands.  It  will  be  seen  that  one 
very  dense  band  occupies  a largo  portion  of 
