Couple (mechanics)

“ The Couple.—If two equal parallel forces act upon a body along different lines in opposite directions, as in Fig. 68, they have no single resultant or there is no one force that will have the same effect as the two components acting together. A combination of forces of this kind is called a couple. Its tendency is to produce change of rotation in a body. An example is the action upon a compass needle which is rotated by a force which urges one end toward the north and by an equal force which urges the other end toward the south. ”

“ It is understood, of course, that the couples have no components (in the generalized sense) except of the types indicated; for instance, they may consist in each case of a force applied to the top at a point of the axis, and of the accompanying reaction at the pivot. ”

“ In the position just described, if the wife has her arms around her lover's body and her heels in his knee-pockets, while he supports himself by his elbows and knees over and above her, resting none of his weight upon her, it is perfectly easy for her to lift her hips up and down, or sway them from side to side, or swing them in a circling "round-and-round" [pg 82] motion, as she may choose to do. She can thus originate her half of the in-and-out motion—a something she will delight to do, if given a fair chance. ”

“ A couple is said to be right or left handed with reference to the observer, according to the direction in which it tends to turn the body, and is a driving couple or a resisting couple according as its tendency is with or against that of the actual rotation. ”

“ The bride’s resistance is just as real a force as is the gravity in a pile of stones. At the bottom of that pile of stones his bride’s soul waits and he has to remove them one by one; actions which take as concrete an amount of psychic energy as if they could be measured in foot-pounds or kilowatt hours. ”

“ Sliding Contact: Forms of the Teeth of Spur-wheels and Racks.—A line of connexion of two pieces in sliding contact is a line perpendicular to their surfaces at a point where they touch. Bearing this in mind, the principle of the comparative motion of a pair of teeth belonging to a pair of spur-wheels, or to a spur-wheel and a rack, is found by applying the principles stated generally in §§ 36 and 37 to the case of parallel axes for a pair of spur-wheels, and to the case of an axis perpendicular to the direction of shifting for a wheel and a rack. ”

“ A Couple consists of a moving particle, raised to the degree M.A., and combined with what is technically called a 'better half.' The following are the principal characteristics of a Couple: (1) It may be easily transferred from point to point. (2) Whatever force of translation was possessed by the uncombined particle, (and this is often considerable,) is wholly lost when the Couple is formed. ”

“ Valets and ladies'-maids will soon learn how to put them in place, the axle of the cylinder upon the two supports of the motor, and will carry them to master or mistress at the hour of awakening. Lying soft and warm upon their pillow they may hear it all, as if in a dream — foreign telegrams, financial news, humorous articles, the news of the day. ”

“ All the married women present, except perhaps a few very old and decrepit ones, join hands, the two brideswomen taking the bride between them. Thus forming a wide circle, they dance backward and forward, round and round the room, sometimes forming a knot in the center, sometimes far apart with outstretched arms, till suddenly, either by accident or on purpose, the chain is broken through at one place, which is the signal for all to rush out into the court-yard, still holding hands. ”

“ The goodwife, in linsey-woolsey short gown and red petticoat, steps lightly back and forth in calf pumps beside the great wheel, or poises gracefully to give a final twist to the long-drawn thread of wool or tow. The continuous buzz of the flax wheels, harmonizing with the spasmodic hum of the big wheel, shows that the girls are preparing a stock of linen against their wedding day. Less active, and more fitful, rattles the quill-wheel, where the younger children are filling quills for the morrow's weaving. ”

“ Balance to Corners.—All the ladies turn to the right and balance to gentlemen; all the gentlemen turn to the left and balance to ladies. Thus the lady of the head couple will balance with the gentleman of the third couple; the lady of the third couple will balance with the gentleman of the second couple, and so on. The “balance” is performed by taking four steps forward and retiring four steps, then again advancing and turning corner partner once with both hands and retiring to place.
Repeated by head couples and danced twice by side couples. ”

“ A man looking down on the throng sees only couples, but no single persons. Now suppose that by some rule of the dance, at a given signal one man at one end of the room must leave his partner and cling to the wall, whilst at the same moment a woman at the other end of the room must do the same. ”

“ One of the chief advantages of the method of transmitting motion between wheels and axles by straps or cords, is that the wheel and axle may be placed at any distance from each other which may be found convenient, and may be made to turn either in the same or contrary directions. ”

“ In fact, physics teaches us that the hand is a combination of the six mechanical powers--the lever, the wedge, the wheel and axle, the pulley, the screw, and the inclined plane. But the mechanical effect is always depreciated. ”

“ At the bottom, lady gives left hand to her partner, and they promenade back to places at the top of the line. (This figure is frequently omitted.) Top couple advance, courtesy and bow, then lady turns off to the right, gentleman to the left, each followed by the rest of her or his line. Top couple meet at the bottom of figure, join hands, and, raising their arms, let all the other couples pass under them towards the top of the line, till all reach their own places, except the top, who have now become the bottom couple. ”

“ Attached to the axle, and turning with it, is a wheel a with hooks in its circumference, upon which lies a rope; one end of this rope is attached to the circumference of the wheel, and the other supports a weight e. This latter weight may be called the power, while the weight d suspended from the axle is the load. When the power is sufficiently large, e descends, making the wheel to revolve; the wheel causes the axle to revolve, and thus the rope is wound up and the load d is raised. ”

“ Two such forces constitute what is known in mechanical science as a couple, which occasions rotatory instead of rectilinear motion, and can only be neutralised by an equal and opposite couple of forces. ”

“ Two bodies, such for instance as a screw and nut, having such forms that at any instant there is only one possible motion for each relatively to the other, form the simplest combination available for machinal purposes—such bodies he calls a pair of elements. Two or more elements from as many different pairs can be combined into a link, and such links united into kinematic chains, and it is by fixing, that is, preventing the motion of, some one link of such a chain that a mechanism is obtained. ”

“ Position is, at the side of her husband, two paces in advance, and in such position that a side view is had of the form; her body bent forward, so that her hands, which are clasped, will rest on her husband's shoulder, head thrown back, eyes directed to those of her husband, face expressing grief. A few paces to the left of the lady, is a cradle, containing a sleeping child. ”

“ Each guest is stationed at the end of a string and at a signal they begin to wind up the string until they meet their fate at the other end of it.
The lady and gentleman winding the same string will marry each other, conditions being favorable; otherwise they will marry someone else. Those who meet one of their own sex at the other end of the string will be old maids or bachelors. ”

“ Marries Between Twenty-five and Thirty-five
¶ Most Musculars are still unmarried at twenty-five when their Alimentive friends have families and when their Thoracic ones have had a divorce or two. But few Musculars are unmarried at thirty-five, though at that age their Osseous and Cerebral friends are often still single.
The Muscular does not marry on nothing, and as he does not star in any line of work as early in life as the Alimentive or Thoracic he does not have the means to marry as early in life as they. But he is a splendid worker, gets something to do and does it fairly well. ”

“ One train of mechanism may diverge into two or more—as when a single shaft, driven by a prime mover, carries several pulleys, each of which drives a different machine. The principles of comparative motion in such converging and diverging trains are the same as in simple trains.
Division 6.—Aggregate Combinations.
§ 72. General Principles.—Willis designated as “aggregate combinations” those assemblages of pieces of mechanism in which the motion of one follower is the resultant of component motions impressed on it by more than one driver. ”

“ Desirous that my wife should have the advantage of negative gravity while taking our walks, I had removed the machine from the trunk and fastened it inside of the basket, which she could carry under her arm. This assisted her wonderfully. When one arm was tired she put the basket under the other, and thus, with one hand on my arm, she could easily keep up with the free and buoyant steps my knapsack enabled me to take. ”

“ When you give your wife your hand to lift her from the carriage, you grasp a woman of wood: she gives you a “thank you” which puts you in the same rank as her servant. You understood your wife no better before than you do after the ball: you find it difficult to follow her, for instead of going up stairs, she flies up. ”

“ To make this effective, it requires a considerable number of couples, so that there will be at least four lines, constantly passing each other in opposite directions, and forming a very pleasing appearance. When the first couple reach the top of the room, they lead the march round the room again, until all the couples are following them in regular column. ”

“ The real bride watches carefully how the pseudo bride takes her left hand from her father's arm, shifts her fan, or whatever represents her bouquet, from her right hand to her left, and gives her right hand to the groom. In the proper maneuver the groom takes her right hand in his own right hand and draws it through his left arm, at the same time turning toward the chancel. ”

“ F G is the arm, secured to the central shaft, A, upon which are loosely fitted the bevel-wheels C, D. The bevel-wheel B turns freely on F G. Motion may be given to the two wheels C, D to produce aggregate motion of the arm, or to the arm and one of these wheels to produce aggregate motion of the other. ”

“ They cross right arms, each lady taking the hand of the opposite lady. With hands joined, ladies walk round, halting with opposite partners. Turn opposite gentleman with left hand, and return to place, crossing right arms in center as before and turning partner with left hand.
A variation of this figure is sometimes introduced as follows: When the exchange of partners has been effected, instead of resuming positions in quadrille, the head couples remain facing their respective side couples, and a “ladies’ chain” is made on each side of the quadrille by each two facing couples. ”

“ It is often necessary that the rod to which reciprocating motion is communicated shall be urged by the same force in both directions. A wheel partially furnished with teeth, acting on two racks placed on different sides of it, and both connected with the bar or rod to which the reciprocating motion is to be communicated, will accomplish this. Such an apparatus is represented in fig. ”

“ The bridegroom on dismounting walks seven times round the palanquin, the bride’s brother at each turn giving him a cut with an oleander twig, and the women of the family throwing showers of cake from the windows. He retires, and while mounting his horse, and before he is in the saddle, the bride’s father comes out, and, giving him a present, leads him into the marriage-hall.... The girl keeps her eyes closed throughout the whole day, not opening them until the bridegroom is ushered into the marriage-booth, so that the first object she sees is her intended husband. ”

“ Wheels thus proportioned, revolving in exactly the same time, might be all placed on one axle, and would partake of one common motion, or, what is to the same effect, several grooves might be cut upon the face of one solid wheel, with diameters in the proportion of the odd numbers 1, 3, and 5, &c., for the lower pulley, and corresponding grooves on the face of another solid wheel represented by the even numbers 2, 4, 6, &c., for the upper pulley. ”

“ The nature of our present invention consists principally in our providing, instead of that a motive-power wheel having its axis upon fixed bearings in an eccentric position and turning in an oscillating cylinder. ”

“ If the arms are not so fixed as to become horizontal, at the same time; the method of assigning the proportion between the weights is analogous to that made use of above in levers, which make an angle at the point, whereon they are supported.
41. From this case of the lever hung on an axis, it is easy to make a transition to another mechanical power, the wheel and axis. ”