A£ecimteZmt}    Report  on  Ginger  Crops  in  Jamaica.  593 
centre,  and  move  the  fine  adjustment  screw  back  and  forth.  If  the 
illumination  is  central,  then  the  image  will  disappear  and  reappear 
in  a  vertical  direction,  while,  when  out  of  axis,  the  image  will 
"  wobble"  either  to  the  right  or  left.  Adjust  the  mirror  and  the 
relative  position  of  the  source  of  illumination  (if  feasible),  until  the 
image  moves  vertically.  This  method  presupposes  that  the  microm- 
eter screw  works  true.  In  order  to  find  out  whether  this  be  the 
case,  combine  both  methods  :  Make  the  illumination  central  by  the 
first  method,  and  then  see  whether  the  image  wobbles  on  focussing 
up  and  down ;  it  should,  of  course,  not  do  so. 
REPORT  ON  GINGER  CROPS  IN  JAMAICA.1  — 
By  William  Fawcett, 
Director  of  the  Botanical  Department. 
The  quality  of  commercial  ginger  upon  which  the  price  depends 
is  due  chiefly  to  soil,  but  also  to  curing,  to  the  variety,  white  or  blue, 
and  to  whether  it  has  been  freshly  planted  a  few  months  before  or 
has  been  "  ratooning"2  for  one  or  more  years. 
The  soil  which  produces  the  very  highest  quality,  realizing  per- 
haps £\o  per  cwt.  in  London  market,  is  the  very  deep  black  soil  of 
the  virgin  forest. 
Magnificent  trees,  six  feet  in  diameter,  may  be  seen  in  some  dis- 
tricts lying  rotting  on  the  ground,  while  the  ginger  cultivators  have 
gone  further  to  the  centre  of  the  island,  abandoning  the  woodlands 
already  cut  down.  The  plan  adopted  in  cleaning  the  forest  is, 
for  a  cultivator  to  invite  10  to  1 2  of  his  friends  to  a  "  cutting  match;" 
he  provides  food  and  drink,  and  the  laborious  work  of  felling  trees 
is  carried  on  merrily  and  without  much  expense.  Afterwards  fire 
is  put,  and  the  place  is  burnt  over.  This  burning  is  considered  very 
important,  as  much  so  as  the  virgin  soil.  Probably  its  importance 
is  due  principally  to  the  deposit  of  potash  and  other  mineral  mat- 
ters contained  in  the  ashes,  but  the  fire  will  also  sweeten  the  ground, 
correcting  sourness,  and  moreover  it  destroys  insect  pests.  Some 
cultivators  will  only  grow  ginger  in  freshly-cleared  woodland  and 
next  year  they  move  on  to  a  new  clearing,  but  although  in  this  way 
1  From  Bulletin  of  the  Botanical  Department,  Jamaica.    Vol.  I.    Part  6. 
2  Ratoon  ginger  is  that  which  has  grown  on  the  same  ground  for  two  or  more 
years. 
