XVI 
INTRODUCTION, 
the free communication with the outer air, then there 
seems to be no limit to the species we may introduce — 
the beautiful productions of the tropics may be brought to 
our doors. 
How often has it been repeated^ that he who causes an 
ear of wheat to grow where it never grew before, is one 
of the greatest benefactors to mankind ! If this he true, 
must we not also regard as a benefactor the man who has 
introduced the loveliest scenery of nature into the most 
crowded streets of our sooty and muddy metropolis ! who 
has clothed our courtyards, aye, even our windows, with a 
perpetual summer ! who has realized that sweet land of a 
poet’s imagination — 
“ Where a leaf never dies in the still blooming bowers ! ” 
It is Mr. Ward* who has effected this. His plan, 
although improved, I may perhaps say perfected, by various 
accessories, depends primarily and fundamentally on pro- 
tecting the plants from too free communication with the 
outer air. This end is obtained by the use of glass, the 
light so essential to vegetation being thus freely admitted. 
The most ready way to try the experiment is, to procure a 
glass vessel, for instance, one of those jars used by drug- 
gists and confectioners ; introduce some soft sandstone, or 
some light soil, filling one-sixth of the jar with it, and 
taking care that the earth be very moist, yet allowing no 
* See Appendix A. 
