CONTEMPORARY WRITINGS. 
191 
Incrustations in- hot water Apparatus. 
— Notwithstanding that clear soft water only 
may be used in filling an hot water apparatus, 
yet more or less of sediment, and of a hard 
slaty substance will become deposited within a 
few months ; and where less attention is paid 
to the nature of the water employed, the 
deposits will be greater in proportion. To 
prevent this sal ammoniac (or muriate of am- 
monia) should be mixed with the water, at 
the rate of about an ounce to ninety gallons of 
water. 
Rose Forcing. — Provins and Moss Roses 
may be forced annually with the utmost suc- 
cess, without giving them a season of rest. 
The plants are introduced into heat (a shelf 
near the glass in a vinery will do) in succes- 
sion, and as soon as the most forward flowers 
have fully expanded, they are removed to a 
greenhouse stage to display their beauty, and 
to ripen their wood. About the middle or 
end of May, the pots are fully exposed to the 
open air, plunged to the rim in coal-ashes. 
Nothing more is required until the first week 
in October, when the same season's growths 
are to be pruned in to two buds, and the plants 
placed in a shed for a week, to moderately dry 
the soil previous to re- potting them. Then 
the ball is turned out and the soil shaken from 
the roots, the strongest pruned in, but all that 
are fibrous retained. The plants are then re- 
potted in the same sized pots (9-inch), using 
a mixture of two parts strong loam, two parts 
well decomposed cow-dung, and one part rotten 
leaf mould ; and placed under a green-house 
stage, until required for forcing. — G.C 
Oncidium unguiculatum. — This new yel- 
low-flowered oncid is one of the best which 
our gardens contain. It is a strong growing 
species, flow r ering freely; it blooms during the 
winter season ; and the blossoms remain in a 
fresh state for an incredible length of time. 
It was first flowered in August 1846, by 
C. B. Warner, Esq., whose gardener writes 
(Jan. 19) — " It has now on it forty open blos- 
soms, and is likely to continue in blossom for 
another month; it has never had less than 
forty flowers on it since October, and would 
have had many more had not several branches 
been cut for bouquets, for which it is most 
useful. If cut at an early stage of its flower- 
ing it will send out lateral flowering branches 
at the base of those which have been removed. 
As to winter decoration it holds the first rank 
in the orchid house, on account of its beauty 
and the length of time it continues in bloom." 
We can confirm this from our own experience, 
having observed the same individual blossoms 
to last for two or three months. 
Mulberry Trees and Silkworms. — Mrs. 
Whitby, of Newlands, in Hants, has, during the 
last ten years, been directing her attention to 
the rearing of silkworms, with a view to their 
produce, and with considerable success. In 
1836 she procured a number of plants of the 
mulberry of the Philippine Islands (Morns 
alhus, var. multicauUs); she also bought silk- 
worms' eggs at Novi, which is said to produce 
the finest silk in Italy. Some difficulty was 
experienced in winding off the cocoons, and in 
1844, a person acquainted with the process 
was engaged from France, and the result had 
been highly satisfactory in the production of 
silk fit for the loom. At the same time she 
learnt how to treat the mulberry plants : cut- 
tings put into a cucumber frame with a slight 
heat, in October, 1844, and thence transplanted 
into the open ground in the following spring, 
in two years yielded on an average ten cuttings 
each plant, two pounds weight of leaves having 
previously been gathered from each for feeding 
the silkworms. One acre of land planted with 
2,400 mulberry plants will, at the end of two 
years, yield from 20,000 to 24,000 cuttings. 
In 1846 Mrs. Whitby made some experiments 
to ascertain the relative value of eggs procured 
front four different places, and the following is 
the comparative weight and number of cocoons 
produced, all the worms being treated in every 
respect alike. 
Cocoons. 
oz. Cocoons. 
No. 1. English 77 weighed 2, and 77 produced £ raw silk. 
2. Poictiers 55 ,, 2, ,, 4G0 „ 1| 
3. Bourdeaux 47 ,, 2, „ 480 „ 1J „ 
4. Italian 45 „ 2, „ 213 „ 1 „ 
5. Bengal 340 „ 2, „ . . 
The Bengal cocoons were very inferior to the 
others. Mrg. Whitby finally showed how the 
English grower could compete with the Bengal 
grower, the latter having four crops, and the 
former only one annually; one cocoon reared 
in Englrnd being equal in weight to four of 
the Bengal; and the raw silk selling at from 23*. 
to 25s. per lb., while the Bengal raw silk 
fetches only from 10s. to lis. per lb. 
Cocoa Disease. — According to the Jamaica 
papers the cocoa of that country, presumed to 
be the Caladhim esculentum- (or Colocasia 
escidenta), is destroyed by a disease similar to 
that of the potato. The Cocoa, or Syre, grows 
from three to seven feet high, and consists ol 
the leaves, the heart, and the fingers, or tubers. 
The disease attacks the head first, the heart of 
which is converted to a black pulp, and at 
length becomes a hollow tube ; the leaves then 
droop and die, and the growth of the fingers, 
or eatable part, stops. There is no peculiarity 
of soil or aspect exempt from destruction ; 
and on examination either of the soil or the 
plant nothing can be discovered to lead in the 
remotest degree to the cause of the disease. 
Strawberries. — The following is an out- 
