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plant linseed oil is expressed; and even the refuse, after the oil is extracted, forms oil-cakes, so valuable in fattening cattle, sheep, and other live stock. From hemp, however, treated in a similar way, we have the materials for cordage, ropes, and cables. Russian hemp is most used, but English hemp, when properly manufactured, is superior to that introduced from the north.

The aim of the rope-maker is to unite the strength of a great number of fibres, and the first part of his process is spinning of rope-yarns; that is, twisting the hemp in the first instance. This is done in various ways, and with different machinery, according to the nature of the intended cordage. We shall confine our description to the manufacture of the larger kinds, such as are used for the standing and running rigging of ships. An alley, or walk, is enclosed for the purpose, about 200 fathoms long, and of a breadth suited to the extent of the manufacture. It is sometimes covered above. At the upper end of this rope-walk is set up the spinningwheel. The band of the wheel goes over several rollers, called whirls, turning on pivots in brass holes. The pivots at one end come through the frame, and terminate in little hooks. The wheel, being turned by a winch, gives motion in one direction to all the whirls. The spinner has a bundle of dressed hemp round his waist, with the two ends meeting before him. The hemp is laid in this bundle in the same way that women spread the flax on the distaff. There is great variety in this; but the general aim is to lay the fibres in such a manner, that, as long as the bundle lasts, there may be an equal number of the ends at the extremity, and that a fibre may never offer itself double, or in a bight. The spinner draws out a proper number of fibres, twists them with his fingers, and, having got a sufficient length detached, he fixes to the hook of a whirl. The wheel is now turned, and the skein is twisted, becoming what is called rope-yarn, and the spinner walks backwards down the ropewalk. The part already twisted draws along with it more fibres out of the bundle. The spinner aids this with his fingers, supplying hemp in due proportion, as he walks away from the wheel, and taking care that the fibres come in equally from both sides of his bundle, and that they enter always with their ends, and not by the middle, which would double them. He should also endeavour to enter every fibre at the heart of the yarn. This will cause all the fibres to mix equally in making it up, and will make the work smooth, because one end of each fibre is, by this means, buried among the rest, and the other end only lies outward; and this, in passing through the grasp of the spinner, who presses it tight with his thumb and palm, is also made to lie smooth. A good spinner endeavours always to supply the hemp in the form of a thin flat skein, with his left hand, while his right hand is employed in grasping firmly the yarn that is twining off, and in holding it tight from the whirl, that it may not run into loops or kinks. It is evident that both the arrangement of the fibres, and the degree of twisting, depend on the skill and dexterity of the spinner, and that he must be instructed, not by a book, but by a

master. The degree of twist depends on the rate of the wheel's motion, combined with the retrograde walk of the spinner. We may suppose him arrived at the lower end of the walk, or as far as is necessary for the intended length of his yarn. He calls out, and another spinner immediately detaches the yarn from the hook of the whirl, and gives it to another, who carries it aside to the reel; and this second spinner attaches his own hemp to the whirl-hook. In the mean time, the first spinner keeps fast hold of the end of his yarn; for the hemp, being dry, is very elastic, and, if he were to let it go out of his hand, it would instantly untwist, and become little better than loose hemp. He waits, therefore, till he sees the reeler begin to turn the reel, and he goes slowly up the walk, keeping the yarn of an equal tightness all the way, till he arrives at the wheel, where he waits with his yarn in his hand till another spinner has finished his yarn. The first spinner takes it off the whirlhook, joins it to his own, that it may follow it on the reel, and begins a new yarn. The second part of the process is the conversion of the yarns into what may with propriety be called a rope, cord, or line. That we may have a clear conception of the principle which regulates this part of the process, we shall begin with the simplest possible case-the union of two yarns into one line.

When hemp has been split into very fine fibres by the hatchet, it becomes exceedingly soft and pliant, and, after it has lain for some time in the form of fine yarn, it may be unreeled and thrown like flaxen yarn, so as to make sewing-thread. It is in this way, indeed, that the sail-makers' sewing-thread is manufactured, and when it has been kept on the reel, or on balls or bobbins, for some time, it retains its twist as well as its uses require. But this is by no means the case with yarns spun for great cordage. The hemp is so elastic, the number of fibres twisted together is so great, and the diameter of the yarn (which is a sort of lever on which the elasticity of the fibre exerts itself) is so considerable, that no keeping will make the fibres retain this constrained position.

The end of a rope-yarn being thrown loose, it will immediately untwist, and this with considerable force and speed. It would, therefore, be a fruitless attempt to twist two such yarns together; yet the ingenuity of man has contrived to make use of this very tendency to untwist, not only to counteract itself, but even to produce another and a permanent twist, which requires force to undo it, and which will recover itself when this force is removed. Every person must recollect that, when he has twisted a packthread very hard with his fingers between his two hands, if he slackens the thread by bringing his hands nearer together, the packthread will immediately curl up, running into loops or kinks, and will even twist itself into a neat and firm cord. The component parts of a rope are called strands, and the operation of uniting them with a permanent twist is called laying or closing, the latter term being chiefly appropriated to cables and other very large cordage.

The process of laying or closing large cordage

is thus conducted: the strands of which the rope is composed consist of many yarns, and require a considerable degree of hardening. This cannot be done by a whirl driven by a wheel-band; it requires the power of a crank turned by the hand. The strands, when properly hardened, become very stiff, and, when bent round the top, are not able to transmit force enough for laying the heavy and unpliant rope which forms beyond it. The elastic twist of the hardened strands must therefore be assisted by an external force. All this requires a different machinery and a different process. At the upper end of the walk is therefore fixed a tackle-board: this consists of à strong oaken plank, called a breast-board, having three or more holes in it and fitted with brass or iron plates. Into these are put iron cranks called heavers, which have hooks or forelocks, and keys on the ends of their spindles. They are placed at such a distance from each other that the workmen do not interfere while turning them round. This breast-board is fixed to the top of strong posts, well secured by struts or braces facing the lower end of the walk. At the lower end is another breast-board fixed to the upright post of a sledge, which may be loaded with stones or other weights. Similar cranks are placed in the holes of this breast-board; the whole goes by the name of the sledge.

The top necessary for closing large cordage is too heavy to be held in the hand, it therefore has a long staff, which has a truck on the end. This rests on the ground, but even this is not enough in laying great cables. The top must be supported on a carriage, where it must lie very steady, and it needs attendance, because the master workman has sufficient employment in attending to the manner in which the strands close behind the top, and in helping them by various methods. The top is therefore fixed to the carriage by lashing its staff to the two upright posts. A piece of soft rope or strap is attached to the handle of the top by the middle, and its two ends are brought back and wrapped several times tight round the rope in the direction of its twist, and bound down. This greatly assists the laying of the rope by its friction, which both keeps the top from flying too far from the point of union of the strands, and brings the strands more regularly into their places. The first operation is warping the yarns. At each end of the walk are frames called warpng frames, which carry a great number of reels, or winches, filled with rope-yarn. The foreman of the walk takes off a yarn end from each, till he has made up the number necessary for his rope or strand, and, bringing the ends together, he passes the whole through an iron ring fixed to the top of a stake driven into the ground, and draws them through; then a knot is tied on the end of the bundle, and a workman pulls it through this ring till the intended length is drawn off the reels. The end is made fast at the bottom of the walk, or at the sledge, and the foreman comes back along the skein of yarns, to see that none are hanging slacker than the rest. He takes up in his brand such as are slack and draws them tight, keeping them so till he reaches the upper end, where he cuts the yarns

to a length, again adjusts their tightness, and joins them all together in a knot, to which he fixes the hook of a tackle, the other block of which is fixed to a firm post, called the warpingpost. The skein is well stretched by the tackle, and then separated into its different strands. Each of these is knotted apart at both ends. The knots at their upper ends are made fast to the hooks of the cranks in the tackle-board, and those at the lower ends are fastened to the cranks in the sledge. The sledge itself is kept in its place by a tackle, by which the strands are again stretched in their places and every thing adjusted, so that the sledge stands square on the walk, and then a proper weight is laid on it. The tackle is now cast off, and the cranks are turned at both ends in the contrary direction to the twist of the yarns (in some kinds of cordage the cranks are turned the same way with the spinning twist). By this the strands are twisted and hardened up, and as they contract by this operation the sledge is dragged up the walk. When the foreman thinks the strands sufficiently hardened, which he estimates by the motion of the sledge, he orders the heavers at the cranks to stop. The middle strand at the sledge is taken off from the crank; this crank is taken out, and a stronger one put in its place. Tire other strands are taken off from their cranks, and all are joined on the hook which is now in the middle hole; the top is then placed between the strands, and, being pressed home to the point of their union, the carriage is placed under it, and it is firmly fixed down; some weight is taken off the sledge. The heavers now begin to turn at both ends; those at the tackle-board continue to turn as they did before, but the heavers at the sledge turn in the opposite direetion to their former motion, so that the cranks at both ends are now turning one way. By the motion of the sledge-crank the top is forced away from the knot, and the rope begins to close. The heaving at the upper end restores to the strands the twist which they are constantly losing by the laying of the rope. The workmen judge of this by making a chalk mark on the intermediate points of the strands, where they lie on the stakes which are set up along the walk for their support. If the twist of the strands is diminished by the motion of closing they will lengthen, and the chalk mark will move away from the tackle-board; but, if the twist increases by turning the cranks at the tackle-board, the strands will shorten and the mark will come nearer to it. As the closing of the rope advances the whole shortens, and the sledge is dragged up the walk. The top moves faster, and at last reaches the upper end of the walk, the rope being now laid.

In the mean time the sledge has moved several fathoms from the place where it was when the laying began. These motions of the sledge and top must be exactly adjusted to each other. The rope must be of a certain length, therefore the sledge must stop at a certain place. At that moment the rope should be laid; that is, the top should be at the tackle-board. In this consists the address of the foreman. He has his attention directed both ways. He looks at the strands,

and, when he sees any hanging slacker between the stakes than the others, he calls to the heavers at the tackle-board to heave more upon that strand. He finds it more difficult to regulate the motion of the top. It requires a considerable force to keep it in the angle of the strands, and it is always disposed to start forward. To prevent or check this, some straps of soft rope are brought round the staff of the top, and then wrapped several times round the rope behind the top, and kept firmly down by a lanyard or bandage. This both holds back the top and greatly assists the laying of the rope, causing the strands to fall into their places, and keep close to each other, which is sometimes very difficult, especially in ropes composed of more than three strands. It will greatly improve the laying the rope, if the top has a sharp, smooth, tapering pin of hard wood, pointed at the end, projecting so far from the middle of its smaller end that it gets in between the strands which are closing. This supports them, and makes their closing more gradual and regular. The top, its notches, the pin, and the warp or strap, which is lapped round the rope, are all smeared with grease or soap, to assist the closing. The foreman judges of the progress of closing chiefly by his acquaintance with the walk, knowing that when the sledge is a-breast of a certain stake the top should be a-breast of a certain other stake. When he finds the top too far down the walk he slackens the motion at the tackle-board, and makes the men turn briskly at the sledge. By this the top is forced up the walk, and the laying of the rope accelerates, while the sledge remains in the same place, because the strands are losing their twist, and are lengthening, while the closed rope is shortening. When, on the other hand, he thinks the top too far advanced, and fears that it will be at the head of the walk before the sledge has got to its proper place, he makes the men heave briskly on the strands, and the heavers at the sledge crank work softly. This quickens the motion of the sledge by shortening the strands; and, by thus compensating what has been overdone, the sledge and top come to their places at once, and the work appears to answer the intention. When the top approaches the tackle-board the heaving at the sledge could not cause the strands immediately behind the top to close well, without having previously produced an extravagant degree of twist in the intermediate rope. The effort of the crank must, therefore, be assisted by men stationed along the rope, each furnished with a tool called a woolder. This is a stout oaken stick, about three feet long, having a strap of soft rope-yarn or cordage, fastened on its middle or end. The strap is wrapped round the laid rope, and the workman works with the stick as a lever, twisting the rope round in the direction of the crank's motion. The woolders should keep their eye on the man at the crank, and make their motion correspond with his. Thus they send forward the twist produced by the crank, without either increasing or diminishing it, in that part of the rope which lies between them and the sledge. Such is the general and essential process of rope making.

The fibres of hemp are twisted into yarns, that they may make a line of any length, and stick among each other with a force equal to their own cohesion. The yarns are made into cords of permanent twist by laying them; and that we may have a rope of any degree of strength many yarns are united in one strand, for the same reason that many fibres were united in one yarn ; and in the course of this process it is in our power to give the rope a solidity and hardness which make it less penetrable by water, which would rot it in a short while. Some of these purposes are inconsistent with others: and the skill of a rope-maker lies in making the best compensation, so that the rope may, on the whole, be the best in point of strength, pliancy, and duration, that the quantity of hemp in it can produce. The following rule for judging of the weight which a rope will bear is not far from the truth. It supposes them rather too strong; but it is so easily remembered that it may be of use. Multiply the circumference in inches by itself, and take the fifth part of the product, it will express the tons which the rope will carry. Thus, if the rope has six inches circumference, six times six is thirty-six, the fifth of which is seven tons and one-fifth.

It is usual in cables, and in other cases, to have recourse to the operation of tarring. This is often done in the state of twine or yarn, as being the best mode by which the hemp can be uniformly penetrated. The yarn is made to wind off from one reel, and, having passed through a vessel of liquid hot tar, is wound on another reel; the superfluous tar is taken off by passing through a hole surrounded with oakum: or it is sometimes tarred in skeins, which are drawn by a capstern through a tar-kettle, and a hole formed by two plates of metal, held together by a lever, loaded with a weight. There is this peculiarity to be noticed -tarred cordage is weaker, when new, than white, and the difference increases by the keeping. From some very accurate experiments made more than half a century ago, it was found that, on newly-made cordage, the white was one-eighth stronger than that which was tarred; that, at the expiration of three months, the difference in favor of the new was almost one-fourth; and, in about three years and a half, the difference was as twenty-nine to eighteen. From these, and other experiments, it was ascertained, 1. That white cordage in continual service is one-third more durable than that which is subjected to the operation of tarring. 2. That it retains its strength much longer while kept in the warehouse. 3. That it resists the ordinary injuries of the weather one-fourth longer. It may then be asked, Why is tar ever used by the rope-maker? Because white cordage, when exposed to be alternately very wet and dry, is weaker than that which is tarred, and to this cables and groundtackle are continually subjected. It has also been pretty well ascertained that cordage which is only superficially tarred is constantly stronger than that which is tarred throughout.

Before we conclude this article we may notice Mr. Chapman's method of making ropes and cordage, for which he obtained, some years since,

his majesty's letters patent.

The specifications may be found in the ninth volume of the First Series of the Repertory. It is too long to be admitted in our work; the following is, however, an outline of the whole :

Rope-yarns are spun either by hand, or by machinery in the practice of the first method rope-walks are necessary, and the fibres of the hemp are drawn into the yarn of different lengths proportionate in a given degree to their position on the outside or inside of the yarn; accordingly, when this yarn is strained, and its diameter collapses, the inside fibres of hemp bear the greatest strain, and thus they break progressively from the inside. In the spinning by a mill the fibres are all brought forward in a position parallel to each other, previously to their receiving their twist. They are consequently all of one length; and, when twisted, the outside fibres are most shortened by forming the same number of spirals round a greater axis than the interior, and thus they must consequently break the first, on the same principle that the outside yarns of strands of ropes manufactured in the old method break before the interior yarns; and consequently with less strain than ropes of the improved principle, where the strands (or immediate component parts of the rope) have been formed in such a manner as that all the yarns shall bear equally at the time of the rope's breaking. Nevertheless yarns spun by a mill have been found stronger than common yarns, on account of the great evenness with which they are spun; the manual labor in manufacturing is much less than in the common method: but on the other hand there is the expense of machinery, and the greater waste of hemp in preparing it for being drawn out in the progressive stages of its advance to the spindle. The method invented by Mr. Chapman differs from both the preceding, in causing, by an easy and simple contrivance, the fibres of the hemp to be laid in the yarn in such a manner as the yarns themselves are laid in the strands of the rope manufactured on the new principle. The machinery consists only of a spindle divided into two parts, the upper containing apparatus to draw forward the hemp from the spinner with twist sufficient to combine the fibres; which enables him to employ women, children, and invalids, and also to appropriate the rope-ground solely to the purpose of laying ropes. maining parts of the invention consist chiefly in giving from a stationary power internal motion to a loco-motive machine, viz. to the roper's sledge, on which the strands and the rope itself are twisted, by which contrivance they are enabled to apply a water-wheel or steam-engine to the whole process of making ropes of all kinds

whatever.

The re

Mr. Huddart likewise obtained a patent for an improved method of registering or forming strands in the machinery for manufacturing of cordage; which he effects in the following manner-1. By keeping the yarns separate from each other, and drawing them from bobbins which revolve to keep up the twist whilst the strand is forming. 2. By passing them through a register, which divides them by circular shells of holes; the number in each shell being agree

able to the distance from the centre of the strand, and the angle which the yarns make with a line parallel to it, and which gives them a proper position to enter. 3. A cylindrical tube which compresses the strand, and maintains a cylindrical figure to its surface. 4. A gauge to determine the angle which the yarns in the outside shall make with a line parallel to the centre of the strand when registering; and, according to the angle made by the yarns in this shell, the length of all the yarns in the strand will be determined. 5. By hardening up the strand, and thereby increasing the angle in the outside shell, which compensates for the stretching of the yarns and the compression of the strand.

ROPE-YARN, among sailors, is the yarn of any rope untwisted, but commonly made up of junk: its use is to make sinnet, mats, &c.

ROQUELAURE, n. s. Fr. roquelaure. A cloak for men.

Within the roquelaure's clasp thy hands are pent. Gay.

RORAAS, an inland town of Norway, in the bishopric of Drontheim. It stands on a high mountain the most elevated inhabited situation in the country. Frost and snow prevail during almost the whole year. It contains 3000 inhabitants, principally occupied in the copper mines of the neighbourhood. Sixty-seven miles S. S. E. of Drontheim.

RO'RID, adj. Lat. roridus. Dewy.

A vehicle conveys it through less accessible cavities into the liver, from thence into the veins and so in a rorid substance through the capillary cavities. Brown's Vulgar Errours.

RORIDULA, in botany, a genus of the monogynia order, and pentandria class of plants: COR. pentapetalous: CAL. pentaphyllous: CAPS. bivalved; the antheræ scrotiform at the base. Species one only, a Cape shrub.

ROSA (Salvator), a celebrated painter, born in Naples in 1614. He was first instructed by Francis Francazano, a kinsman: but the death of his father reduced him to sell drawings sketched upon paper, one of which falling into the hands of Lanfranc, he took him under his protection, and enabled him to enter the school of Spagnoletto, where he was taught by Daniel Falcone, a distinguished painter of battles at Naples. Salvator had a fertile imagination. He studied nature with attention and judgment; and always represented her to the greatest advantage. He was equally eminent for painting battles, animals, sea or land storms; and he executed these different subjects in a style altogether unequalled. His pieces are exceedingly scarce and valuable; one of the finest is that representing Saul and the witch of Endor, which was preserved at Versailles. He died in 1673; and, as his paintings are in few hands, he is more generally known by his prints; of which he etched a great number. They are chiefly historical. He is said to have spent the early part of his life among a troop of banditti; and that the rocky desolate scenes in which he was accustomed to take refuge furnished him with those romantic ideas in landscape, in the representation of which he so greatly excels. His robbers, as his detached figures are commonly called, are supposed also

to have been taken from the life. He was also a musician; as appears from his musical MSS. purchased at Rome by Dr. Burney.

ROSA, in botany, the rose, a genus of the polygamia order, and icosandria class of plants; natural order thirty-fifth, senticosa: CAL. urceolated, quinquefid, corneous, and straightened at the neck; petals five. The SEEDS are numerous, hispid, and affixed to the inside of the calyx. The different kinds of roses are very numerous; and botanists find it very difficult to determine with accuracy which are species and which are varieties. On this account Linné, and some other eminent authors, are inclined to think that there is only one real species of rose, which is the rosa canina, or dog-rose of the hedges, &c., and that all the other sorts are accidental varieties of it. However, according to the Linnæan arrangement, they stand divided into fourteen species, each comprehending varieties, which in some sorts are but few, in others numerous. The supposed species and their varieties, according to the arrangement of Gmelin, are as follow:

1. R. alba, the common white rose, grows five or six feet high, having a green stem and branches, armed with prickles, hispid pedunculf, oval smooth germina, and large white flowers. The varieties are, large double white rose, dwarf single white rose, maiden's-blush white rose, being large, produced in clusters, and of a white and blush red color.

2. R. alpina, the alpine inermous rose, grows five or eight feet high, having smooth or unarmed reddish branches, pinnated seven-lobed smooth leaves, somewhat hispid pedunculi, oval germina, and deep-red single flowers; appearing in May. This species, as being free from all

kind of armature common to the other sorts of roses, is esteemed as a singularity; and from this property is often called the virgin or thorn

less rose.

3. R. canina, the canine rose, wild dog-rose of the hedges, or hep-tree, grows five or six feet high, having prickly stalks and branches, pinnated, five or seven-lobed leaves, with aculeated foot-stalks, smooth pedunculi, oval smooth germina, and small single flowers. There are two varieties, red-flowered and white-flowered. They grow wild in hedges abundantly all over the kingdom; and are sometimes admitted into gardens, to increase the variety of the shrubbery collection.

4. R. Carolinensis, the Carolina and Virginia rose, &c., grows six or eight feet high, or more, having smooth reddish branches, very thinly aculeated; pinnated seven-lobed smooth leaves, with prickly foot-stalks; somewhat hispid pedunculi, globose hispid germen, and single red flowers in clusters, appearing mostly in August and September. The varieties are, dwarf Pennsylvanian rose, with single and double red flowers, and American pale-red rose. This species grows naturally in different parts of North America, and often continues in blow from August until October; and the flowers are succeeded by numerous red berry-like heps in autumn, causing a variety all winter.

5. R. centifolia, the hundred-leaved red rose,

&c., grows from about three or four to six or eight feet high, with pinnated three and fivelobed leaves; and large very double red flowers, having very numerous petals, and of different shades in the varieties. The varieties are, common Dutch hundred-leaved rose, grows three or four feet high, with erect greenish branches, but moderately armed with prickles; and large remarkably double red flowers, with short regularly arranged petals. Blush hundred-leaved rose, grows like the other, with large very double pale-red flowers. Provence rose grows five or six feet with greenish-brown prickly branches, and very large double globular red flowers, with large petals folding over one another, more or less in the varieties. The varieties are, common red Provence rose, and pale Provence rose; both of which having larger and somewhat looser petals than the following sort:-cabbage Provence rose; having the petals closely folded over one another like cabbages. Dutch cabbage rose, very large. Childing Provence rose. Great royal rose, grows six or eight feet high, producing remarkably large, somewhat loose, but very elegant flowers. All these are large double red flowers, somewhat globular at first blowing, becoming gradually a little spreading at top, and are very ornamental fragrant roses. Moss Provence rose, supposed a variety of the common rose; grows erectly four or five feet high, having brownish stalks and branches, very closely armed with short prickles, and double crimson-red flowers; having the calyx and upper part of the peduncle surrounded with a rough mossylike substance, effecting a curious singularity. This is a fine delicate rose, of a high fragrance, which, together with its mossy calyx, renders it a most beautiful flower.

6. R. cinnamonea, the cinnamon rose, grows five or six feet high, or more, with purplish branches thinly aculeated; pinnated five or seven lobed leaves, having almost inermous petioles, smooth pedunculi, and smooth globular germina; with small purplish red cinnamon-scented flowers early in May. There are varieties with double flowers.

7. R. eglanteria, the eglantine rose or sweet briar, grows five or six feet high, having green branches, armed with strong spines sparsedly; pinnated seven-lobed odoriferous leaves, with acute folioles and rough foot-stalks, smooth pedunculi, globular smooth germina, and small pale-red flowers. The varieties are, common single flowered, semi-double flowered, doubleflowered, blush double-flowered, and yellowflowered. This species grows naturally in some parts of Ergland, and in Switzerland. It claims culture in every garden for the odoriferous property of its leaves: and should be planted in the borders, and other compartments contiguous to walks, or near the habitation, where the plants will impart their refreshing fragrance very profusely around; and the young branches are excellent for improving the odor of nosegays and bow-pots.

8. R. gallica, the gallican rose, &c., grows from about three or four to eight or ten feet high, in different varieties; with pinnated, three, five, or seven-lobed leaves, and large red and

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