Blue is one of the seven colours into which the rays of light divide themselves when refracted through a glassprism, seen in nature in the clear expanse of the heavens; the term is also applied to a dye or pigment of this hue.
The substances used as blue pigments are of very different natures, and derived from various sources; they are all compound bodies, some being natural and others artificial. They are derived almost entirely from the vegetable and mineral kingdoms. The principal blues used in painting are ultramarine, which was originally prepared from lapis-lazuli or azure-stone - a mineral found in China and other oriental countries - but, as now prepared, it is an artificial compound of china-clay, carbonate of soda, sulphur, and charcoal; Prussian or Berlin blue, which is a compound of cyanogen and iron; blue bice, prepared from carbonate of copper; indigo blue, from the indigo plant. Besides these, there are numerous other blues used in art, as blue-verditer, smalt- and cobalt-blue, from cobalt, lacmus or litmus, etc.
Before the discovery of aniline or coal-tar colours dyers chiefly depended for their blues on woad, archil, indigo, and Prussian blue, but now a series of brilliant blues are obtained from coal-tar, possessing great tinctorial power and various degrees of durability.
Blue as a colour ranges from green-blue (turquoise) through to purple-blue (indigo).
Alice blue - A very light greenish-blue colour.
Aquamarine - A bluish-green colour.
Azure - A deep blue colour reminiscent of the sky.
Aquamarine - A pale greenish-blue colour.
Bice blue - A medium blue colour
Cambridge blue - A light blue colour.
Cobalt blue - A deep blue colour with a greenish-tint. The colour of old blue glass.
Bog is the name given to a piece of wet, soft, and spongy ground, where the soil is composed mainly of decaying and decayed vegetable matter. Such ground is valueless for agriculture until reclaimed, but often yields abundance of peat for fuel.
A bog seems usually to be formed as follows: A shallow pool induces the formation of aquatic plants, which gradually creep in from the borders to the deeper centre. Mud accumulates round their roots and stalks, and a semi-fluid mass is formed, well suited for the growth of moss, particularly Sphagnum, which now begins to luxuriate, continually absorbing water, and shooting out new plants above as the old decay beneath; these are consequently rotted, and compressed into a solid substance, gradually replacing the water by a mass of vegetable matter. A layer of clay, frequently found over gravel, assists the formation of bog by its power of retaining moisture. When the subsoil is very retentive, and the quantity of water becomes excessive, the superincumbent peat sometimes bursts forth and floats over adjacent lands.
Bogs are generally divided into two classes: red bogs, or peat-mosses, and black bogs, or mountain mosses. The former class are found in extensive plains frequently running through several counties, such as the Chatmoss in Lancashire, and the Bog of Alien in Ireland, the depth varying from 3.6 to 13 metres. Their texture is light and full of filaments, and is formed by the slow decay of mosses and plants of different kinds. The lower parts, being more entirely decayed, approach nearer to the nature of the humus than the upper portion, and, as being more carbonaceous, are more valuable for fuel. Black bog is formed by a more rapid decomposition of plants. It is heavier and more homogeneous in quality, but is usually found in limited and detached portions, and at high elevations where its reclamation is difficult.
In Ireland bogs frequently rest on a calcareous subsoil, which is of great value in reclaiming them. In the reclamation of bog land a permanent system of drainage must be established; the loose and spongy soil must be mixed with a sufficient quantity of mineral matter to give firmness to its texture and fertilize its superabundant humus; proper manures must be provided to facilitate the extraction of nutriment from the new soil, and a rotation of crops adopted suitable for bringing it into permanent condition. The materials best adapted for reclaiming peat are calcareousearths, limestonegravel, shell-marl, and shell-sand. Thoroughly reclaimed bogs are not liable to revert to their former condition. Trunks of trees are often found in bogs as are also bones of extinct animals. Research Bog
The Bridgewater Treatises were a series of books, the outcome of the will of the Reverend Henry Francis, Earl of Bridgewater, who died in 1829, bequeathing a sum of 8000 pounds, which should be paid to the person or persons chosen to write and publish 1000 copies of a work on the power, wisdom, and goodness of God as manifested in the creation. The result was eight works on animal and vegetablephysiology, astronomy, geology, the history, habits, and instincts of animals, etc, which at one time enjoyed great popularity. The names of the writers are Dr. Chalmers, Dr. Kidd, Dr. Whewell, Sir Charles Bell, Dr. Roget, Dr. Buckland, Reverend William Kirby, and Dr. Prout. Research Bridgewater Treatises
Coconut oil is a solid vegetable fat, largely used in candle-making and in the manufacture of soaps and pomatum. This fat is got by pressure from the albumen of the coconut kernel, and is as white as lard, and somewhat firmer. Research Coconut Oil
Coumarin is a vegetable proximate principle, obtained from the Dipterix odordta or Tonka bean, sweet woodruff, sweet-scented vernalgrass, melilot, etc. It has a pleasant aromatic odour, and a burning taste. It is used in perfumery, in medicine, and to give flavour to certain varieties of Swiss cheese. Research Coumarin
Death is that state of a being, animal or vegetable, but more particularly of an animal, in which there is a total and permanent cessation of all the vital functions, when the organs have not only ceased to act, but have lost the susceptibility of renewed action. Death takes place either from the natural decay of the organism, as in old age, or from derangements or lesions of the vital organs caused by disease or injury. The signs of actual death in a human being are the cessation of breathing and the beating of the heart; insensibility of the eye to light, pallor of the body, complete muscular relaxation, succeeded by a statue-like stiffness or rigidity which lasts from one to nine days; and decomposition, which begins to take place after the rigidity has yielded, beginning first in the lower portion of the body and gradually extending to the chest and face. What becomes of the mind or thinking principle, in man or animal, after death, is a matter of philosophical conjecture or religious faith. Research Death
Dyeing is the art of giving colour to textile and other articles in such a way that the colours are more or less permanent, and not readily affected by the action of light, washing, etc. Like spinning and weaving it was originally a home industry, as it still is in many places. Until about 1850 natural dye-stuffs alone were employed, but the discovery of dyes of all colours that can be obtained from coal-tar products revolutionized dyeing as an industry, and the vegetable dye-stuffs were gradually superseded by the newer colours.
Before dyeing, the materials have generally to be cleansed or bleached to get rid of undesirable colouring matters or impurities; and frequently a textile material is subjected to some subsidiary treatment in order to obtain special effects. For example, cottonyarn may be subjected to the action of strong causticsoda ('mercerizing' process) while in a state of great tension, in order to give it a permanent silky lustre.
Dyeing is not only an art, it is also a branch of applied chemistry. One fundamental principle is, that the colouring matter and other necessary substances must be applied in a state of solution, and while in direct contact with the fibre they must be rendered insoluble, so that they are precipitated within or upon the fibre and thus permanently fixed. The method of effecting this varies greatly according to the fibre and the colouring matter employed. As a rule the vegetable and the animal fibres are dyed by very different methods. The affinity of the animal fibres for certain colouring matters is often so great that they are readily dyed by simple immersion in hot colour solutions;
but this simple process is not generally sufficient. According to the method of their application in dyeing the following groups: of dye-stuffs may be distinguished: Avid Colours, Basic Colours, Direct Colours, Developed Colours, Mordant Colours, Miscellaneous Colours, Reactive Colours.
The acid colours are so called because they are of an acid character and are applied in an acid dye-bath. As a rule, they are only suitable for dyeing the animal fibres, e.g. wool and silk, also leather, horn, feathers, etc. Only a few vegetable dye-stuffs belong to this class, for example, the purple colour orchil and the blue colour indigo extract. On the other hand, the acid colours derived from coal-tar - and increasingly petroleum - are very numerous and yield a great variety of hues - red, orange, yellow, green, blue, violet, brown, and black, each with its particular name.
The basic colours are so called because their essential constituents, to which they owe their dyeing power, are organicbases. The bases themselves are colourless and too insoluble in water to be of use, hence they are employed in the form of their soluble coloured salts, usually the hydrochlorides of the colour-bases. Their solutions are precipitated by tannic acid, because it combines with the colour-bases to form insoluble tannates. Wool, silk, and animal substances generally have a direct attraction for colour-bases, and hence these fibres are readily dyed by simple immersion in hot aqueous solutions of the basic colours. Cotton and linen, on the other hand, are not dyed so readily; they need first to be prepared or impregnated with tannic acid, and thus prepared are said to be mordanted, the tannic acid in this connection being styled the mordant. Most of the colours of this class are fugitive to light, and all but one, barberryroot, are derived from coal-tar products.
The direct colours are so called because they dyecotton direct, that is, without the aid of any mordanting process. The first of this class derived from coal-tar was congo red, discovered in 1884; this group includes a very great variety of fast colours, and forms, indeed, one of the most important and valuable series of dye-stuffs employed. Cotton, linen, and the vegetable fibres generally are dyed in the simplest possible manner by merely boiling them in a solution of the dye-stuff, with or without the addition of a little soap, carbonate or sulphate of soda, etc. Wool and silk are frequently dyed in the same manner as cotton. Very few vegetable dye-stuffs belong to the direct colours, e.g. Safflower, Turmeric, Saffron, Annatto. They are all fugitive, and have been of little or no importance to the dyer since the end of the 19th century. The coal-tar colours of this class, on the other hand, are extremely numerous.
The developed colours include a variety of colours which are formed in situ upon the fibre by the successive application of two or more substances. These colours are all of coal-tar origin. A number of them belong to the so-called azo colours, derived from compounds containing nitrogen.
The mordant colours form one of the most important classes of colouring matters, for they include not only most of the vegetable dye-stuffs, e.g. madder, logwood, fustic, etc, but also many valuable fast coal-tar colours, commonly known as the alizarin colours, after their typical representative, alizarin. These mordant colours have by themselves very little colouring power, as a rule, and if employed alone in dyeing give little or no result. If applied, however, in conjunction with metallic salts, notably those of chromium, aluminium, iron, tin, and copper, they each yield a variety of colours, according to the metallic salt employed. In employing them usually two distinct operations are involved: first, that of applying the metallic salt or mordant, called the mordanting process ; and second, that of dyeing proper, in which the mordanted material is boiled in a solution or decoction of the dye-stuff. During the dyeing operation the colouring principle of the dye-stuff combines with the metallic salt already upon the material, and the colour is thus produced and fixed upon the fibre. The method of mordanting varies with the fibre and the metallic salt employed. The vegetable dye-stuffs of this class include Madder, Sapanwood, Camwood, Barwood, Old Fustic, Young Fustic, Quercitron Bark, Persian Berries, Weld, Logwood. Madder was formerly the most important and highly valued of the dye-stuffs of this class, being especially employed to produce the fine 'Turkey-red' dye; but was entirely superseded by the coal-tar colour alizarin towards the end of the 19th century.
Reactive colours combine directly with the fibre being dyed through a chemical reaction and result in a fast colour. The first ranges of reactive dyes for cellulose fibres were introduced in the mid-1950s.
Similarly, the employment of cochineal (an insect dye) has also greatly diminished through the introduction of the cheaper colours. Camwood and barwood are almost entirely used in wool-dyeing, either in conjunction with the indigo-vat or for the purpose of dyeing various shades of brown. Old fustic is the most important of the yellow mordant dye-stuffs, and the colours are fast although not very brilliant. Young fustic yields fugitive colours, and has been little used since 1900. Quercitron bark is an excellent dye-stuff employed by wool-dyers for the production of bright orange and yellow colours. Persian berries and weld, a species of wild mignonette, are both excellent dye-stuffs, but their employment is now limited. Logwood is largely employed by wool, silk, and cotton dyers for dyeing black and dark-blues, which, although fast to washing, are only moderately so towards light. During the 20th century dyewoods were gradually replaced by coal-tar colours.
Among miscellaneous colours are several dye-stuffs applied in a distinct manner. Indigo is a dark-blue powder quite insoluble in water, but can be rendered soluble for dyeing purposes by two methods. The first method converts the indigo into so-called indigo extract, which is sold as a blue paste and applied as an acid colour in dyeing wool and silk. In the second method the indigo-blue is converted into indigo-white, which readily dissolves in the alkalipresent, the solution thus obtained being called an indigo-vat. If cotton, wool, or silk is steeped for some time in the clear yellow solution of such a vat, and then exposed to the oxidizing influence of the air, they are dyed a permanent blue. The indigo-white absorbed by the fibre loses its acquired hydrogen, and thus insoluble indigo-blue is regenerated within and upon the fibre. Aniline black is a valuable colour, produced direct upon the fibre by the oxidation of aniline, and remarkable for its extreme permanency.
Catechu is a vegetable dye-stuff used in dyeing cotton and woollen brown. On wool, catechu yields khaki browns in single bath by using copper sulphate as the mordant. On silk it is largely employed for weighting purposes in the process of dyeing black. Chrome Yellow, Iron Buff, Prussian Blue, and Manganese Brown, employed in cotton dyeing, are frequently classed as mineral colours. Chrome yellow is obtained by immersing cotton successively in solutions of acetate of lead and bichromate of potash, whereby the yellow precipitate of chromate of lead is fixed upon the fibre. Iron buff is obtained in a similar manner by the successive application of iron sulphate and carbonate of soda, and finally developing the full colour by washing with water and exposure to air. The buff colour is really due to the precipitation of oxide of iron on the cotton. Prussian blue is at once developed by passing the buff-dyed cotton through an acidified solution of potassium ferrocyanide. The production of manganese brown on cotton is similar to that of iron buff. The brown colour ultimately produced upon the fibre is an oxide of manganese. The mineral colours are very useful for certain purposes, and are to be regarded as very fast to light. Research Dyeing
Eau de Cologne is a perfume said to have been invented by the Italian chemist, Johann Maria Farina, who settled at Cologne in 1709. The original recipe is unknown, though several chemists in Cologne have long claimed to be the sole owners of it. The general principle of Eau de Cologne is alcoholic vegetable extracts, essential oils and rectified spirits. The usual recipe prescribes twelve drops of each of the essential oils, bergamot, citron, neroli, orange and rosemary, with one dram of Malabar cardamoms and a gallon of rectified spirits which are distilled together. Later recipes used highly purified spirits and made further distillation unnecessary. Research Eau de Cologne
Function is the specific office or action which any organ or system of organs is fitted to perform in the animal or vegetable economy. Vital functions are functions immediately necessary to life, as those of the brain, heart, lungs, etc. Natural or vegetative functions, functions less instantly necessary to life, as digestion, absorption, assimilation, expulsion, etc. Animal functions are those which relate to the external world, as the senses, voluntary motions, etc. Research Function
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Matt and Leela Probert
Abbreviations
Research Bog
