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Cooperage is the making of wooden vessels by binding strips or staves of wood with hoops to form cylinders (barrels, casks etc.). The art probably started for preserving wine. The coopers of London were incorporated in 1501.
 Research Cooperage
Soil erosion is the wearing away and redistribution of the Earth's soil layer. It is caused by the action of water, wind, and ice, and also by improper methods of agriculture. If unchecked, soil erosion results in the formation of deserts (a process known as desertification). It has been estimated that 20% of the world's cultivated topsoil was lost between 1950 and 1990. If the rate of erosion exceeds the rate of soil formation (from rock and decomposing organic matter), then the land will become infertile.
The removal of forests (the process of deforestation) or other vegetation often leads to serious soil erosion, because plant roots bind soil, and without them the soil is free to wash or blow away, as in the American dust bowl. The effect is worse on hillsides, and there has been devastating loss of soil where forests have been cleared from mountainsides, as in Madagascar. Improved agricultural practices such as contour ploughing are needed to combat soil erosion. Windbreaks, such as hedges or strips planted with coarse grass, are valuable, and organic farming can reduce soil erosion by as much as 75%. Soil degradation and erosion are becoming as serious as the loss of the rainforest.
Research Soil Erosion
Tinsel is a shining metallic material used in thin strips or threads to give a sparkling effect in decorations.
Research Tinsel
A trug is a shallow garden basket made of wooden strips and with a handle extending from side to side.
Research Trug
Morello cherry (Prunus cerasus), also known as dwarf cherry and sour cherry, is a deciduous shrub or small tree of the family Rosaceae native to Asia. The leaves are alternate, ovate, dark green and glossy above and finely serrated. The flowers are small, white or pinkish in colour, with bud scales and leaf- like bracts at the base and grow in clusters on shortened twigs. The fruit is an edible, dark-red coloured, globose, bitter drupe. The bark is brownish- red in colour, smooth, and peels off in strips around the trunk and spreading or ascending branches.
Research Morello Cherry
South Sea Arrowroot (Tacca pinnatifida) is a perennial herb of the natural order Taccaceae native to the East Indies and Society Islands. It has a tuberous root stock, which like that of the potato and rice is rich in starch. The leaves are large and cut into oval segments, the flowers are purplish in colour, funnel-shaped and clustered in a dense umbel and succeeded by large, pear-shaped, ribbed fruits. Strips of the leaves are plaited into hats, but mainly the plant is grown for the starch which is obtained by rasping the tubers and macerating the material in water, the resulting deposit being a fine form of arrowroot.
Research South Sea Arrowroot
There are several methods of controlling bleeding during surgical operations. 1. When an incision is made, much of the bleeding comes from the skin edges and from subcutaneous tissue: small towels are often used, clipped to the edges of the wound to protect the cut surface, and prevent the repeated rubbing away of clot which would otherwise occur. These are called variously 'side-towels','skin towels' or 'tetra towels'. The latter term arose as these towels are commonly attached with four- pronged forceps ('tetra forceps'). 2. By pressure. As the surgeon makes his incision, he or his assistant applies a gauze swab to the raw area. Capillary and most venous bleeding stops almost immediately, and does not re-start unless the surface is rubbed. 3. Pressure forceps (artery forceps) are applied to the cut ends of arteries, as little of the surrounding tissue as possible being included in the jaws of the forceps.
These bleeding points are dealt with at some later stage in the operation in one of four ways. (i) The artery forceps are simply removed. Bleeding does not recur as the crushed end of the vessel has sealed itself off. (ii) Surgical diathermy current is applied to the pressure forceps, thus coagulating the end of the blood vessel. (iii) A surgical ligature is tied round the tissue included in the forceps which are then removed. (iv) A stitch is inserted and tied round the tissue held in the forceps in order to secure more firmly the end of the cut vessel. 4. The surgical diathermy is used to make the incision through the muscle and deep tissue layers. This technique is used especially in the treatment of cancer and particularly in the removal of vascular structures such as the breast. Small blood vessels are thus sealed as the tissue is divided. 5. The application of gauze soaked in adrenaline solution. This drug constricts the ends of the vessels and is particularly useful in the nose.
Where extensive bleeding may be expected - such as in plastic operations on the face - the operation area is sometimes infiltrated with a saline solution of adrenaline. By the time the effect of the adrenaline has passed off, the divided vessels have become blocked by clots. 6. The application of hot packs. The combination of pressure and heat speeds the clotting process and the retraction of the cut ends of vessels. 7. Thromboplastin released by enzymes from damaged tissue is essential to start the clotting process. There is very little damage in a clean surgical incision and thromboplastin formation can be brought about by the surgeon taking a small piece of muscle, and pulping it by repeated crushing with pressure forceps. This ' muscle graft' is applied to the bleeding area. Purified thrombin is supplied in powder in sterile ampoules ready to mix with sterile water: the solution is then applied with a swab or a spray and is particularly useful under skin grafts where it acts as a kind of glue. Fibrin foam is another preparation used extensively in neurosurgery where even a small amount of bleeding into the brain or nerve, may do irreparable damage. Gelatin 'sponge' supplied in small biscuit-like strips, can be used in bleeding cavities or tied to the surface of a bleeding organ. The sponge acts as an artificial network in which clotting occurs and the substance is itself absorbed.
Oxycel (oxidised cellulose) acts in a similar way and promotes rapid clotting. It is used in such sites as the prostatic cavity and can be tied around the catheter which is left in place at the end of operation. Calcium alginate is a similar preparation and is manufactured from sea-weed. The raw oozing surface is moistened with one solution which is then activated by spraying with a second solution containing calcium. All these artificial coagulants are only of use for 'low pressure' bleeding - that is from capillaries or small veins.
Research Surgical Haemostasis
Chaff is a device comprising strips of metal foil, used to confuse enemy radar systems including those in guided missiles.
Research Chaff
The RPG-43 was a Soviet anti-tank grenade. The RPG-43 was designed for use at very close range, and consists of a cylindrical metal case containing 612 grams of TNT connected to a metal sleeve containing two fabric strips which provide stability in flight. The RPG-43 was used by Egyptian forces during the war in 1973 against Israel.
Research RPG-43
The Dutch process (or stack process) was formerly the principal method by which white lead was prepared. It consisted building a stack of earthenware pots containing acetic acid upon a thick layer of spent tan or manure and placing strips or coils of metallic lead over the pots; boards were then laid to forma false floor over the whole and more stacks built on top. The entire structure was then sealed and over time the metallic lead converted into lead carbonate by corrosion caused by the action of the acetic acid vapour in the presence of carbon dioxide.
Research Dutch Process
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The Probert Encyclopaedia was designed, edited and programed by
Matt and Leela Probert
©1993 - 2009 The Probert Encyclopaedia
Southampton, United Kingdom
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