458 
VARIETIES. 
On  the  Growth  of  Plants  in  Closely  Glazed  Oases.  By  N.  B.  Ward, 
F,  R.  S.,  &c.  Second  edition.  London  :  Van  Voorst,  1852.  pp.  143, 12mo. 
— The  first  edition  of  this  little  treatise,  published  in  1842,  is  doubtless 
well  known  to  many  of  our  readers ;  and  some  may  remember  Mr.  "Ward's 
original  account  of  his  interesting  discovery  of  a  method  of  growing  every 
sort  of  plant  in  the  dun  atmosphere  of  the  smokiest  part  of  London,  pub- 
lished in  the  Companion  to  the  Botanical  Magazine  in  1836.  This  new 
edition  if  reduced  in  size  is  increased  in  interest,  and  is  embellished  with 
tasteful  illustrations  on  wood,  several  of  them  exhibiting  approved  forms  of 
those  glazed  cases  with  which  the  name  of  our  author  is  inseparably  con- 
nected. The  first  chapter,  on  the  natural  conditions  of  plants,  their  relations 
to  heat,  light  and  moisture,  and  the  necessity  of  attending  to  the  particular 
conditions  or  combination  of  circumstances,  under  which  each  species  flou- 
rishes, is  illustrated  by  ingenious  and  often  novel  observations.  The  second 
chapter  treats  of  the  causes  which  interfere  with  the  natural  conditions  of 
plants  in  large  towns,  and  gives  some  idea  of  the  obstacles  which  prevent 
the  cultivation  of  even  ordinary  plants  in  the  open  air  in  London,  and  to 
some  extent  in  other  large  British  towns.  The  third,  on  the  imitation  of  the 
natural  conditions  of  plants  in  closely  glazed  cases,  tells  us  how  a  simple 
incident  (the  accidental  growth  of  a  seedling  fern  and  a  grass  in  a  glass 
bottle,  in  which  the  chrysalis  of  a  Sphinx  had  been  buried  in  some  moist 
mould),  carefully  and  wisely  reflected  on,  taught  Mr.  Ward  how  to  overcome 
these  obstacles,  and  thus  to  surround  himself  with  his  favorite  plants,  in 
beautiful  vegetation,  while  living  in  one  of  the  murkiest  parts  of  London, 
and  even  to  grow  with  complete  success  such  ferns  as  the  Trichomanes  radi- 
cans,  which  is  utterly  uncultivatable  in  any  other  way.  A  fourth  chapter 
treats  of  the  conveyance  of  living  plants  on  shipboard;  which  brings  to  view 
one  of  the  most  important  practical  applications  of  Mr.  Ward's  discovery. 
Sir  William  Hooker  states  that  "  the  Wardian  cases  have  been  the  means, 
in  the  last  fifteen  years,  of  introducing  more  new  and  valuable  plants  to  our 
gardens  than  were  imported  during  the  preceding  century ;  and  in  the  cha- 
racter of  domestic  green-houses — that  is,  as  a  means  of  cultivating  plants 
with  success  in  our  parlors,  our  halls  and  our  drawing-rooms,  they  have 
constituted  a  new  era  in  horticulture."  Formerly  only  one  plant  in  a  thou- 
sand survived  the  voyage  from  China  to  England.  Recently,  availing  him- 
self of  our  author's  discovery,  Mr.  Fortune  planted  250  species  of  plants  in 
these  cases  in  China,  and  landed  215  of  them  in  England  alive  and  healthful ! 
The  same  person  lately  conveyed  in  this  way  20,000  growing  tea-plants,  in 
safety  and  high  health,  from  Shanghae  to  the  Himalayas.  In  fact  this  mode 
of  conveyance  is  now  so  universally  adopted,  and  has  proved  so  successful, 
whenever  properly  managed,  that  it  is  no  exaggeration  to  say  that,  probably, 
"  there  is  not  a  single  portion  of  the  civilized  world  which  has  not  been  more 
or  less  benefitted  by  the  invention."  An  indispensable  requisite  to  success 
in  the  transmission  of  living  plants  by  this  method  is,  that  the  glazed  cases 
should  be  freely  exposed  to  light.    Where  this  cannot  be  done,  we  must  be 
