THOUGHTS ON PLANTING ROCK-WOIiK.—THE TALLOW TREE OF CHINA. 
51 
Phosphoric acid is rare in most geological formations; soils solely or chiefly composed of these, 
therefore, rarely contain it; hut in soils composed of accumulated remains of vegetables, still more of 
animal substances, phosphoric acid salts abound ; above all, in well-manured garden grounds, where 
they usually exist in higher proportion than the plants normally contain. Plants do not select their 
food, but absorb all the soluble matters in contact with their roots: therefore, when the salts which 
they require for their nutrition are present in wrong proportions, they are forced to take up more than 
they should of certain kinds,—in this case, of phosphates,—and hence inevitably follow morbid deviations 
from the natural modes of growth. 
From this we derive the following general laAV:—The more the proportion of phosphoric salts is 
increased in a soil, either through the mode of origin of the soil, or by its culture, the more will the 
plants growing upon it be inclined to deviate from their original type, to form sports, varieties, &c., 
and finally to be attacked and destroyed by internal diseases.—A. H. 
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THOUGHTS OH PLAHTIHG ROCK-WORK. 
T HERE is as much exercise of mind required in disposing plants on rock-work as there is in building 
the masses of stones together. In fact, the placing of the plants in positions not only to exhibit 
their own beauties and peculiarities, but to bring more visibly into view the forms and colours of the 
rocks, in all their natural irregularity, is a work demanding even more taste and skill than building 
up the stones. 
Plants give animation to rock-work, and are suggestive of many a thought which the bare rocks 
could never impart. The depths of darkest shade should embrace within their stony folds plants of 
light coloured flowers or foliage, to relieve their gloom, and assist the eye in tracing out their intricate 
windings. Cerastium Biebersteinii, with its white leaves and whiter flowers, and procumbent habit 
of growth, is admirably adapted for such a purpose, either planted in a recess or suspended gracefully 
over the front of some stone. Ardbis procumbens is also a beautiful plant for a like purpose, though 
less effective than the former, from its flowers being small and white, and its leaves green ; still its 
close symmetrical character renders it very suitable for setting off some rough irregularly-formed 
stone. Aubrietia purpurea grandifiora, as its name implies, is a charming purple-flowering spring 
plant, differing from its congeners in its larger flowers, and will be seen to best advantage planted on 
some external or prominent part of the rock-work, where its colder-coloured flowers will bring forward 
the rocks; while the white-coloured flowers will add depth and extension to the view, and therefore 
heighten the irregularity of the whole. True to its nature, the eye demands the sunshine as well as 
the shade ; and with our many-sided stones and differently-formed plants, as well as great variety of 
colour amongst flowers, it is in our power to meet the eye’s requirements.— John Caie, Gardener to 
the Dowager Duchess of Bedford, Camden-hill, Kensington . 
♦ 
THE TALLOW TREE OF CHIHA. 
f HE Stillingia sebifera is prized for the fatty matter which it yields; its leaves are employed as a 
black dye; its wood, being hard and durable, is used for printing blocks and various other articles ; 
and finally, the refuse of the nut is employed as fuel and manure. 
It is chiefly cultivated in the provinces of Kiangsi, Kongnain, and Chehkiang. In some districts 
near Hangchan, the inhabitants defray all their taxes with its produce. It grows alike on low alluvial 
plains and on granite hills, on the rich mould at the margin of canals, and on the sandy sea-beach. 
The sandy estuary of Hangchan yields little else. Some of the trees at this place are known to be 
several hundred years old, and though prostrated, still send forth branches and bear fruit. 
In mid-winter when the seed-vessels are ripe, they are cut off with their twigs by a sharp crescen- 
tric knife, attached to the extremity of a long pole, which is held in the hand and pushed upwards 
