18 INTRODUCTION. 
moisture or the dryness of the air. The awns are furnished 
with stiff points all turning toward one end; which extend 
when moist, and shorten when dry. The points, too, prevent 
their receding, so that they are drawn up or forward; as 
moisture is returned, they advance, and so on; indeed, they 
may actually be said to travel forward. The capsules of the 
geranium furnish admirable barometers. Fasten the beard, 
when fully ripe upon a stand, and it will twist itself, or un¬ 
twist, according as the air is moist or dry. The flowers of the 
chickweed, convolvulus, and oxalis, or wood-sorrel, close their 
petals on the approach of rain.” 
Gardens have been the delight of poets in all ages. All 
our poets have sung of flowers. They serve all purposes; and 
we are reminded of the fable of the flowers, where the rose 
says — 
What can a poet do without us ? 
“But it is not poets alone who half-worship flowers. What 
an enthusiastic devotion is that which sends a man from the 
attractions of home, the ties of neighbourhood, the bonds of 
country, to range plains, valleys, hills, and mountains, for a new 
flower ! What a spirit must have animated Hermann, Hassel- 
quist, Tournefort, Linnams, Solander, Saussure, Humboldt, and 
hundreds of those who have sacrificed every personal conveni¬ 
ence and selfish motive for the sake of illustrating the volume 
of nature, and opening almost a new existence upon those 
whose researches are necessarily limited. But the love of 
flowers is not shared exclusively by the poet and the naturalist. 
Oh no ! the little child loves the flower-garden, and watches 
with intense interest the early opening buds, such fair types of 
itself. The young, the middle-aged, and the hoary head, sil¬ 
vered with the snows of threescore years and ten; all, all hang 
