76 
The Kew Gardens and Arboretum contain the largest collec- 
tion of living and dried plants known, obtained from every clime, 
and afford facilities for the study of the science of botany and 
horticulture which no other institution of the kind has been able 
to eclipse, if even to approach. The cost of keeping them up 
amounts to upwards of £25,000 per year. 
Of course to give a detailed description of all the subjects of 
striking interest in these gardens would take up far more time 
than could be possibly devoted to them, even in a fairly compre- 
hensive lecture ; indeed, it would necessitate many visits to Kew 
before the enormous amount of material therein accumulated and 
classified could be even superficially grasped. Nevertheless 
there are certain features which, from their importance and 
bearing on botanical science generally, call for more than a mere 
passing remark; I allude to the various conservatories and the 
museums of economic botany. The palm house of Kew, one of 
the finest and largest in the world, is 362 feet long, 100 feet 
wide, and 66 feet in height, having wings 50 feet wide and 
30 feet high. The central part of this great conservatory is 
encircled by a gallery 33 feet from the ground, and ascended by 
spiral staircases. Visitors are thus enabled to view from above 
the canopy of rich and varied tropical leafage which arches 
over the pathways and obscures the roof. The glass (about 
45,000 square feet) is slightly tinged with green, to obviate the 
scorching effect of direct sunlight. The magnificent collection 
of palms, for the cultivation of which‘the house was primarily 
intended, comprises some hundreds of kinds, but mingled with 
them, towering high or fighting for existence below, there is a 
variety of other tropical vegetation which is marvellous to the 
beholder. 
On a lawn to the north of the palm house is a T-shaped house 
of various temperature, consisting of a central area, occupied by 
the great “ Victoria Regia, or Royal Water Lily,” from South 
America ; two lateral wings, one for economic plants.and one for 
temperate and tropical orchids ; a back wing, used as a tropical 
stove; a compartment for begonias and Gesneracer, and for 
Cape heaths, fig-marigolds, &e. 
No less than 1,400 species of orchids are growing in the Kew 
conservatories, and of the most showy kinds there are perhaps 
eight or ten specimens of each. The most recent enumeration of 
the number of species known, to say nothing of mere varieties or 
hybrids, is said by Sir Joseph Hooker to be upwards of 5,000. 
A succulent house, 200 feet long and 30 feet wide, is mainly 
devoted to those plants of warm and arid countries which are 
characterized either by excessive succulence or by the converse 
condition of extreme dryness and rigidity. The plants in this 
