JOINERY. 268 JOINT LIABILITY. trims, and cabinet-work. The term is becoming obsolete. See Buildi.m;. JOINT (OF. joint, joinct, from Lat. junctus, joint, from jungere, to join ; connected with Gk. ^itrytrimi, zvuynynui, .Skt. yuj, to join, and ulti- mately with Eng. yoke), or Akticllation. In anatomy, the comiection existing between any of the denser component parts of the skeleton, whether bone or cartilage. The stnictnres which enter into the formation of the more complex joints are bone, ligament, cartilage, fibro-car- tilage, and synovial membrane. Bone is the fundamental part of all joints. Ligament is very generally the bond of union between bony seg- ments. Cartilage (either articular, costal, or niembraniform ) is found as a layer between sur- faces or an incrustation upon the opposing ends of bones or as an extension of a bone to reach a given point. Fibro-cartilage is either disposed about the circumference of an articular cavity in order to deepen it. or is connective, or separa- tive. Synovial membranes, when articular, exist as thin sacs containing a little fluid wherewith the joints are lubricated from their position be- tween the opposing bones. Joints vaiy in their degree of motion. They are arranged in tliree classes: (1) Synarthrosis, or immovable joint, of which there are four varieties. (2) Amphiar- ihrosis, or joint of limited motion, also called 'synchondrosis' or 'symphysis,' of which there are three lyjies. (3) Diartlirosis, or freely movable joint, of which there are thiee varieties. Synarthrosis is divided into: (a) Sutura, in which there is a union of bone by a series of processes and indentations which fit closely to- gether. There are three types of sutura: viz. sutura dentata, where the indentations are large and extensive, as in the joint.s between the parietal bones of the skull ; sutura serrata, where the dovetailing is smaller and more regu- lar, as in the suture between the frontal bones in youth ; and sutur.a limbosa, where there is an overlaji|)ing of beveled articular surfaces, as in the joint between the temporal bone and the parietal. (b) Harmonia, in which there is a mere coaptation of two rough bony surfaces, as between the two halves of the upper jaw. (c) Schindylesis, in which a thin plate of bone is inserted into a cleft, as where the rostrum of the sphenoid articulates with the vomer, (d) Gomphosis, in which a bone is implanted firmly into a socket of another bone, as where the teeth are inserted into the alveolar processes of the j.-,w. The three varieties of diarthrosis are: (a) Enarthrosis, or ball-and-socket joint, as in the case of the head of the humerus in the glenoid cavity of the scapula: (b) arthrodia. including all articulations of flat or nearly flat surfaces, as in the joint between the acromion process of the scapula and the clavicle: and (c) ginglymus. or hinge-joint, as in the articulation of the hones of the knee, elbow, and ankle. The joints admit- ting of angiilar. lateral, or rotary motion are all called 'ginglymus.' Some anatomists call articu- lation that admits of rotnry motion diarthrosis rotatorius. Amphiarthrosis includes synchondrosis or inion by cartilage, syndesmosis, or union by ligament, and syssarcosis, or union by muscular tissue. As an example of s^-nchondrosis, the imion between the two bones of the pelvis, in front, is excellent. This is generally termed the ■symphysis pubis.' Joints admit of the following varieties of motion: Flexion, extension, adduc- tion, abduction, rotation, circumduction, and gliding movement. The hinge-joints and ball-and- socket joints arc most useful in securing flexion and extension; the ball-and-socket joints in secur- ing adduction, abduction, circumduction, and rotation; while i^rthrodial joints alone secure gliding movement. JOINT ADVENTURE, ENTERPRISE, or TRADE. A phrase ap])lied at times to a business undertaking by two or more persons, in the na- ture of a jnirliicrship (q.v. ) , but which is limited to a single transaction or set of transactions. It is commonly used, however, of joint unilcrtakings in which tlu' essential element of ])artnership — a business carried on in common with a view of profit — is wanting. An example of this class is afforded by an agreement between the owner of an invent ion and another to tiike out a patent in their joint names and sell the right to use it, dividing the profits. Such persons are not car- rv'ing on a business, but are engaged in a joint adventure. Pooling arrangements between com- petitors in business are ordinarily joint enter- prises and not partnerships. Each comiietitor remains sole owner and manager of his separate business, while all are jointly interested in the pool made up of their various earnings. Consult the authorities referred to under Pabtneeship; Contract. JOINT-ILL, or Omphalophlebitis. A dis- ease of young calves, occurring within a few months after birth. The symptoms consjst in swelling of one or more joints. The animals are stiff and lie down the greater part of the time. High fever and rapid i)ulse and breathing are characteristic. The disease arises from infection in the navel at the time of birth or soon after, and a purulent discharge from the navel is seen in all advanced cases. The infection spreads through the umbilical vein, and abscesses may ultimately be formed in the muscles near the navel or even in the lungs and liver. The ma- jority of such cases end in death. In order to prevent the occurrence of the disease the stables shoidd be kept clean and the navel should be treated with antiseptic solutions immediately after birth. Swollen joints may be daily painted with tincture of iodine; internal doses of qui- nine and hyposulphite of soda three times a day sometimes give good result.s. JOINT LIABILITY. A mutual or common responsibility of two or more persons for some act or duty, which so binds them all that one cannot be held or released without the others. It is the direct opposite of 'several liability,' where an individual is bound personally, irrespec- tive of his relations to others. Persons more frequently become jointly and severally liable on a bond or other obligation. In such cases the obligee or owner of the bond or obligation can sue either separately, or both together at his option, Where judgment is recovered against persons jointly liable only, the judgment creditor can ]ey execution against the goods of either or both of them at his option, but can have only one satisfaction. In either of the above cases if the judgment is satisfied out of the goods of one. that one is entitled to contribution from the other, that is, to be reimbursed the proportionate
