Bongardia is a genus of the barberry family. It is a small stemless plant found in Greece and the Middle East. The Iraqis roast or boil the tuberous underground root and eat it. The leaves are also eaten like sorrel. Research Bongardia
To boil is to heat a fluid up to the point at which it is converted into vapour. The conversion takes place chiefly at the point of contact with the source of heat, and the bubbles of vapour rising to the surface, and breaking there, produce the commotion called ebullition. At the ordinary atmospheric pressure ebullition commences at a temperature which is definite for each liquid. The escape of the heated fluid in the form of vapour prevents any further rise of temperature in an open vessel when the boiling point has been reached. The exact definition of the boiling-point of a liquid is 'that temperature at which the tension of its vapour exactly balances the pressure of the atmosphere.' The influence of this pressure appears from experiments. In an exhausted receiver the heat of the human hand is sufficient to make water boil; while, on the contrary, in Papin's digester, in which it is possible to subject the water in the boiler to a pressure of three or four atmospheres, the water may be heated far above the normal boiling point without giving signs of ebullition. From this relation between the ebullition of a liquid and atmospheric pressure the heights of objects above sea-level may be calculated by comparing the actual boiling point at any place with the normal boiling point.. The boiling-point of water as marked on Fahrenheit's thermometer is 212 degrees; on the Centigrade, 100 degrees; on the Reaumur, 80 degrees. Ether boils at about 96 degrees Fahrenheit, mercury at 662 degrees Fahrenheit. Research Boil
Dr Angus Smith's process is a method of treating ferrour metal objects to prevent corrosion. The process consists of heating the article to 300 degrees Fahrenheit as soon as it is cast, and then immersing it in a prepared solution of coaltar which is then brought to the boil and allowe dto continue to boil until all the ammoniacal liquor, water and lighter oils have been expelled. Research Dr Angus Smith's Process
Effervescence, the rapid escape of a gas from a liquid, producing a turbulent motion in it, and causing it to boil up. It is produced by the actual formation of a gas in the liquid, as in fermentation, or by the liberation of a gas which has been forced into it, as in aerated beverages. Research Effervescence
Litharge is lead monoxide (PbO). It is a toxic red or yellow coloured substance prepared by oxidising lead in a current of air at a high enough temperature for the oxide to be melted as it forms. Litharge was used as a drier for paint and in the production of boil oil and terebine. Research Litharge
A preserving jar is a glass jar covered with a glass cap seated on a flat rubber ring used for keeping fruit in an eatable condition for a long time. Clean fruit and water are placed in the jar, leaving a small air space at the top. Several of these jars are placed in a large vessel of cold water, which is then slowly brought to the boil. During this process the glass caps with their rubber rings are loosely held in position by a metal screw cap. About 10 minutes boiling is generally sufficient to sterilise the fruit and to cause air to be driven from the jars by steam from the water inside. The screw caps are then tightened and the jars removed from the water. After cooling, the space at the top of the jars contains only water vapour at low pressure. As a result, the glass cap is then firmly pressed down by atmospheric pressure. No bacteria-laden air can afterwards enter, and so the contents remain in good condition for a long period. When the jars have cooled the presence of the metal cap is not strictly necessary, as the seal is
now maintained by atmospheric pressure. Research Preserving Jars
Vacuum distillation is a distillation process used for materials that have very high boiling-points or are likely to decompose below their boiling-point. Air is evacuated from the apparatus with a vacuumpump, and the vacuum so formed causes the materials being heated to boil at a temperature lower than they would under normal atmospheric pressure. This enables distillation to take place at lower temperatures. One example of its use is in petroleum refining. Research Vacuum Distillation
Coffee is the seed of an evergreen shrub which is cultivated in hot climates, and is a native of Abyssinia and of Arabia. This shrub (Coffea arabica) is from 4 to 6 meters in height, and belongs to the Rubiaceae. The leaves are green, glossy on the upper surface, and the flowers are white and sweet-scented. The fruit is of an oval shape, about the size of a cherry, and of a dark-red colour when ripe. Each of these contains two cells, and each cell a single seed, which is the coffee as we see it before it undergoes the process of roasting.
Great attention is paid to the culture of coffee in Arabia. The trees are raised from seed sown in nurseries and afterwards planted out in moist and shady situations, on sloping grounds or at the foot of mountains. Care is taken to conduct little rills of water to their roots, which at certain seasons require to be constantly surrounded with moisture. When the fruit has attained its maturity cloths are placed under the trees, and upon these the labourers shake it down. They afterwards spread the berries on mats, and expose them to the sun to dry. The husk is then broken off by large and heavy rollers of wood or iron. When the coffee has been thus cleared of its husk it is again dried in the sun, and, lastly, winnowed with a large fan, for the purpose of clearing it from the pieces of husks with which it is intermingled. A pound of coffee is generally more than the produce of one tree; but a tree in great vigour will produce 3 or 4 lbs.
The best coffee has its name from Mocha, on the Red Sea. It is packed in large bales, each containing a number of smaller bales, and when good appears fresh and of a greenish-olive colour. Next in quality to the Mocha coffee may perhaps be ranked that of Southern India and that of Sri Lanka, which is strong and well flavoured; but comparatively little coffee now comes from Sri Lanka. Indonesia and Central America produce large quantities of excellent coffee. Brazilian coffee, though produced more abundantly than any other, stands at the bottom of the list as regards quality. Liberian coffee may also be mentioned. American coffee holds in the judgment of all Orientals the very last rank.
The Dutch were the first to extend the cultivation of coffee beyond the countries to which it is native. About 1690 some coffee seeds were brought to Java, where they were planted and produced fruit. By 1718 the Dutch planters of Surinam had entered on the cultivation of coffee with success, and ten years after it was introduced from that colony by the English into Jamaica, and by the French into Martinique. It was not until 1774 that the planters of Brazil, now the greatest producers of coffee in the world, commenced its cultivation.
Coffee as an article of diet is of but comparatively recent introduction. To the Greeks and Romans it was wholly unknown. From Arabia it passed to Egypt and Turkey, whence it was introduced into England by a Turkeymerchant named Edwards in 1652, whose Greek servant, named Pasqua, first opened a coffee-house in London. In 1671 an Armenian named Pascal set up a coffee-house in Paris. The excellence of coffee depends in a great measure on the skill and attention exercised in roasting it. If it be too little roasted it is devoid of flavour, and if too much it becomes acrid, and has a disagreeable, burned taste. Coffee is used in the form either of an infusion or decoction, of which the former is decidedly preferable, both as regards flavour and strength. The fine aromatic oil which produces the flavour and strength of coffee is lost by boiling. The best mode is to pour boiling water through the coffee in a biggin or strainer, which is found to extract nearly all the strength; or to pour boiling water upon it and set it upon the fire, not to exceed ten minutes. Prepared in either way it is fine and strong.
In the Asiatic mode of preparing coffee the beans are pounded, not ground; and though the Turks and Arabsboil the coffee, they traditionally boil each cup by itself and only for a moment, so that the effect is much the same as that of infusion. In Arabia some additional spicing, generally of saffron or some aromatic seeds, is considered indispensable; but neither Turks nor Arabians use sugar or cream with coffee.
Coffee acts as a nervous stimulant, a property which it owes mainly to the alkaloidcaffeine. It thus promotes cheerfulness and removes languor, and also aids digestion; but in some constitutions it induces sleeplessness and nervous tremblings. Research Coffee
The Probert Encyclopaedia was designed, edited and programed by
Matt and Leela Probert
Abbreviations
Research Bongardia
