ROSCOEA. 
cordage (particularly when new) is highly hygro- 
metric, and expands and contracts in its length 
to a great extent by being dry and wet. The 
damp state constantly producing contraction, 
and the dry one extension. This contraction by 
wetting exercises so much force, that if a rope is 
fully stretched in its dryest state, and then 
wetted, it will break, or tear away the parts to 
which the ends are attached if they are less 
strong than the rope. If, therefore, a mast was 
braced in its proper position by dry white ropes, 
a shower of rain would probably bend the mast 
or break the ropes. On the contrary, if the mast 
was braced as tightly as possible by damp ropes, 
a few hours sunshine would render it quite loose. 
Anything therefore that will destroy the hygro- 
metric properties of the rope by rendering it 
less, or not at all absorbent of humidity, will be 
beneficial in such cases; and tar or paint answers 
this purpose. 
Ropes are always sold and valued by weight, but 
are described by their circumference in inches. 
Thus what is called a 3 inch rope would only 
be about 1 inch in diameter, and when a 24 
inch cable is spoken of (being the largest size 
usually made), a cable less than 8 inches in dia- 
meter is understood. See LeatHEer-Banps. 
ROPE-GRASS. See Restio. 
ROSA. See Ross. 
ROSA MARIA. See Anasrarica. 
ROSCOEA. A genus of ornamental, tropical, 
perennial-rooted, herbaceous plants, of the scita- 
mineous order. Five species, all about a foot 
high, and carrying purple flowers in July and 
August, and thriving best in a soil of sandy loam, 
were introduced to British collections about 28 
years ago from Nepaul. | 
ROSE,—botanically Rosa. A large genus of 
ornamental, calyciflorous shrubs, constituting 
the type of the natural order Rosacez. This 
order is, in a very considerable degree, identical 
with the Linnzan class Icosandria; and though 
of very great extent, and quite naturally distri- 
butable into distinct groups or tribes, it possesses 
remarkable uniformity of botanical character,— 
insomuch that all its genera, no matter how di- 
verse in habit or how peculiar in general appear- 
ance, may be considered as mere proximate and 
easy variations from the true rose genus. It is at 
once one of the largest, one of the most magnifi- 
cent, and one of the most grateful of all the na- 
tural orders. It comprises many plants of rich 
and diversified medicinal virtue,—some plants of 
considerable utility in the arts,—multitudes of 
plants of rare beauty and elegance and fragrance, 
—very many of the most valuable or most orna- 
mental plants of hedges, shrubberies, and plea- 
sure-grounds,—and all the most important fruit- 
trees and fruit-shrubs of the temperate regions 
of the world. Hight tribes, and about 50 genera, 
and nearly 1,000 species of it, besides myriads 
| of varieties of its finest flowering and fruiting 
| plants, at present occur in Britain; and more 
ROSE. 
than three-fifths of all the species are hardy 
shrubs or hardy trees,—and a good deal more 
than one-fourth are hardy herbs,—while only 
about one-ninth require the protection of the 
greenhouse or the stove. The tribes which con- 
tain the greatest number of genera are dryadex, 
sanguisorbee, and pomacee; two tribes which 
contain each only one genus are rosez and neu- 
rade; and the other three tribes are amygda- 
lew, spirezaceze, and chrysobalanee. Some of 
the best known or most interesting genera, addi- 
tional to the true rose genus, are the strawberry, 
the potentilla, the bramble, and the avens, be- 
longing to the tribe dryadeze,—the great burnet 
and the ladies’ mantle, belonging to the tribe 
sanguisorbeze,—the hawthorn, the medlar, the 
quince, the cotoneaster, the loquat, and the pear 
and apple and service, belonging to the tribe 
pomaceze,—and the almond, the peach, the apri- 
cot, the plum, and the cherry, belonging to the 
tribe amygdalee. 
The petals of a rose are five in number; the 
calyx is pitcher-shaped, five-cleft, fleshy, and 
contracted in the neck; and the seeds are nu- 
merous and hispid. ‘Twenty-two species grow 
wild in Britain; about 100, or upwards, have 
been introduced from other countries; and about 
40 more are known. Hybrids and varieties of 
most of the finer species have also ‘been multi- 
plied beyond number. A few of the species, 
comprising a multitude of varieties, are ever- 
green shrubs; a few, comprising very many va- 
rieties, are either climbing or trailing shrubs; and 
the vast majority, as well of species as of varie- 
ties, are upright deciduousshrubs. One subgenus, 
represented by the Scotch rose, has equal, nu- 
merous, bractless prickles, persistent connivent 
sepals, and scarcely any disc; another, repre- 
sented by the Cinnamon rose, is bracteate and 
unarmed, and has glandless lanceolate leaflets, 
and a slender disc; a third, represented by the 
Provence or hundred-leaved rose, has unequal 
bracteate prickles, rugose leaflets, and a thick 
disc surrounding the throat; a fourth, represent- 
ed by the rusty sweet briar, has arched branches, 
unequal prickles, glandular leaflets, persistent 
sepals, and a thick disc; a fifth, represented by 
the dog-rose, has arched branches, equal hooked 
prickles, glandless leaves, deciduous sepals, and 
a disc surrounding the throat; a sixth, repre- 
sented by the villous rose, has erect branches, 
straight prickles, persistent connivent sepals, 
and a thick disc surrounding the throat; a 
seventh, represented by the clustered-styled rose, 
has its styles joined into a long column, and has 
also adnate stipules; and four other but very 
small subgenera, aggregately comprising less 
than a dozen species, have characters different 
from all these seven and from one another. But 
the families into which horticulturists and flor- 
ists and nurserymen distribute roses amount to 
upwards of thirty, and comprise only the orna- 
mental sorts, and have little or no reference to 
fo 
eon 
0g I Rp i ee eee 
7, 
