The blind are those who want, or are deficient in, the sense of sight. Blindness may vary in degree from the slightest impairment of vision to total loss of sight; it may also be temporary or permanent. It is caused by defect, disease, or injury to the eye, to the optic nerve, or to that part of the brain connected with it. Old age is sometimes accompanied with blindness, occasioned by the drying up of the humours of the eye, or by the opacity of the cornea, the crystalline lens, etc. The blind are often distinguished for a remarkable mental activity, and a wonderful development of the intellectual powers. Their touch and hearing, particularly, become very acute.
As early as 1260 an asylum for the blind (L'hospice des Quinze-Vingts) was founded in Paris by St Louis for the relief of the Crusaders who lost their sight in Egypt and Syria; but the first institution for the instruction of the blind was the idea of Valentin Hauy, brother of the celebrated mineralogist. In 1784 he opened an institution in which the blind were instructed not only in appropriate mechanical employments, as spinning, knitting, making ropes or fringes, and working in paste-board, but also in music, in reading, writing, ciphering, geography, and the sciences. For instruction in reading he procured raised letters of metal; for writing he used particular writing-cases, in which a frame, with wires to separate the lines, could be fastened upon the paper; for ciphering there were movable figures of metal, and ciphering-boards in which the figures could be fixed; for teaching geographymaps were prepared upon which mountains, rivers, cities, and the boundaries of countries were indicated to the sense of touch in various ways, etc.
Similar institutions were soon afterwards founded in Amsterdam, Berlin, Brussels, Copenhagen, Dresden, Edinburgh, Liverpool, London, Vienna, and in many towns of the United States. By 1900 there were comparatively few large cities that did not possess a school or institution of some kind for the blind.
At the start of the 20th century the attitude towards the blind was rather patronising, and one source may be quoted as saying 'the occupations in which the blind are found capable of engaging are such as the making of baskets and other kinds of wicker-work, brushmaking, rope and twine making, the making of mats and matting, knitting, netting, fancy work of various kinds, cutting fire-wood, the sewing of sacks and bags; the carving of articles in wood, etc'. However, it was also recognised that more skilled tasks could also be performed by blind persons, and the same source notes that 'Piano-tuning is also successfully carried on by some, and the cleaning of clocks and watches has even been occasionally practised by them'.
Around 1900 an impetus was given, in Britain, to the higher education of the blind by the formation of the British and Foreign Blind Association, the establishment of a college for the Blind Sons of Gentlemen at Worcester, and the Royal Normal College and Academy of Music for the Blind, Upper Norwood.
Various systems were devised for the purpose of teaching the blind to read, some of which consisted in the use of the ordinary Roman alphabet, with more or less modification, and some of which employ types quite arbitrary in form. In all systems the characters rise above the surface of the paper so as to be felt by the fingers. The type adopted by Hauy was the script or italic form of the Roman letter. This was introduced into England by Sir C. Lowther, who printed the Gospel of St. Matthew in 1832 with type obtained from Paris. Before this Gall of Edinburgh made use of an embossed alphabet based on the ordinary Roman small letters, in which all curves were replaced by angular lines, and in 1834 he published the Gospel of St John in this character. Subsequently he introduced various improvements, and in particular the letters were produced with serrated surfaces, thus giving greater distinctness. Alston of Glasgow, Howe of Boston, and others also used the Roman form; but the former (who was the first to print the whole Bible, in 1840) adopted the Roman capitals, while the latter adopted the small letters, printing in this type the Bible and many other books. Of alphabets deviating entirely or nearly so from the Roman letter, one consists of a stenographic shorthand invented by Lucas of Bristol; another was a phonetic shorthand devised by Frere of London. In Dr. Moon's alphabet some of the characters are Roman, others are based on or suggested by the Roman characters. The Braille system, widely adopted by the laye 20th century, is one in which the letters are formed by a combination of dots. Dr. Moon's system from its simplicity and the size of its characters is in very general use in books for the blind. There are also systems by which the blind are enabled to write, and the writing may be either in relief so as to be read by the blind, or in characters that may be read by those who see. Research Blind
There is evidence of the use of crystal balls as a means of divination in medieval times, and 'scrying' in some of its many forms was by no means rare in the Greek and Roman periods. The essential requisite for the exercise of this species of divination is a polished surface of some sort upon which the scryer shall gaze intently; for this purpose mirrors, globules of lead or mercury, polished steel, the surface of water, and even pools of ink, have been employed and have been found to ensure quite as satisfactory results as the crystal ball. The points of light reflected from the polished surface serve to attract the attention of the gazer and to fix the eye until, gradually, the optic nerve becomes so fatigued that it finally ceases to transmit to the sensorium the impression made from without and begins to respond to the reflex action proceeding from the brain of the gazer. In this way the impression received from within is apparently projected and seems to come from without.
It is easy to understand that the results must vary according to the idiosyncrasy of the various scryers; for everything depends upon the sensitiveness of the optic nerve. In many cases the effect of prolonged gazing upon the brilliant surface will simply produce a loss of sight, the optic nerve will be temporarily paralysed and will as little respond to stimulation from within as from without; in other cases, however, the nerve will be only deadened as regards external impressions, while retaining sufficient activity to react against a stimulus from the brain centres. It is almost invariably stated that, prior to the appearance of the desired visions, the crystal seems to disappear and a mist rises before the gazer's eye. The Achaians, as Pausanius relates, frequently used a mirror to divine diseases or to learn whether there was danger of sudden death. Research Crystal Gazing
Entomology is the branch of zoology dealing with insects. It was started as a science in 1705 by the publication of Ray's 'Methodus Insectorum'.
The name entomology comes from the Greek entoma, animals 'cut in', the transverse division or segmentation of the body being their most conspicuous feature.
The true insects are those animals of the division Arthropoda or Articulata distinguished from the other classes of the division by the fact that the three divisions
of the body - the head, thorax, and abdomen - are always distinct from one another. There are never more than three pairs of legs in the perfect insect, and these are all borne upon the thorax. Each leg consists of from six to nine joints. The first of these is called the 'coxa,' and is succeeded by a short joint called the 'trochanter.' This is followed by a joint, often of large size, called the 'femur,' succeeded by the 'tibia,' and this has articulated to it the 'tarsus', which may be composed of from one to five joints.
Normally two pairs of wings are present, but one or other may be wanting. The wings are expansions of the sides of the second and third sections of the thorax, and are attached by slender tubes called 'nervures'.
In the beetles the anterior pair of wings becomes hardened so as to form protective cases for the posterior membranous wings, and are called in this condition ' elytra ' or ' wing-cases.' Respiration is effected by means of air-tubes or tracheas, which commence at the surface of the body by lateral apertures called 'stigmata' or 'spiracles,' and ramify through every part of the body.
The head is composed of several segments amalgamated together, and carries a pair of feelers or 'antennae', a pair of eyes, usually compound, and the appendages of the mouth. The thorax is composed of three segments, also amalgamated, but generally pretty easily recognized. The abdominal segments are usually more or less freely movable upon one another, and never carry locomotive limbs; but the extremity is frequently furnished with appendages connected with generation, and which in some cases serve as offensive and defensive weapons (stings).
The organs of the mouth take collectively two typical forms, the masticatory and the suctorial, the former exemplified by the beetles, the latter by the butterflies, in which the mouth is purely for suction. The alimentarycanal consists of the oesophagus or gullet, a crop, a gizzard, a stomach, and an intestine, terminating in a cloaca. There is no regular system of blood vessels ; the most important organ of the circulation is a contractile vessel situated dorsally and called the 'dorsal vessel.' The nervous system is mainly composed of a series of ganglia placed along the ventral aspect of the body and connected by a set of double nerve-cords.
The sexes are in different individuals, and most insects are oviparous. Reproduction is generally sexual, but non-sexual reproduction also occurs. Generally the young are very different from the full-grown insect, and pass through a 'metamorphosis' before attaining the mature stage. When this metamorphosis is complete it exhibits three stages - that of the larva, caterpillar, or grub, that of the pupa or chrysalis, and that of the imago or perfect winged insect.
Insects have been divided into three sections - Ametabola,Hfemimetabola, and Holometabola, according as they undergo no metamorphosis, an incomplete one, or a complete one. The young of the Ametabola differ from the adult only in size. They are all destitute of wings; the eyes are simple and sometimes wanting. The Hemimetabola undergo an incomplete metamorphosis, the larva differing from the imago chiefly in the absence of wings and in size. The pupa is usually active, or if quiescent capable of movement. In the Holometabola the metamorphosis is complete, the larva, pupa, and imago differing greatly from one another in external appearance and habits. The larva is wormlike and the pupa quiescent. The section Ametabola (which in the opinion of many naturalists are scarcely within the pale of the true Insecta) is divided into three orders - Anoplura (lice), Mallophaga (bird-lice), and Thysanura (springtails). The section Hemimetabola comprises the orders Hemiptera (cicadas, bugs, plant-lice, etc), Orthoptera (cockroaches, crickets, grasshoppers, locusts, earwigs, etc), and Neuroptera (dragon-flies, may-flies, white-ants, etc). The Holometabola comprises the orders Aphaniptera (fleas), Diptera (gnats, bot-flies, gad-flies, mosquitos, house-flies, etc), Lepidoptera (butterflies and moths), Hymenoptera (bees, wasps, and ants), Strepsiptera (stylops, minute and parasites), and Coleoptera (ladybirds, glow-worms, cockchafers, weevils, and all of the beetle tribe).
A division is sometimes made into Mandibulate and Haustellate groups, the oral apparatus of the former being adapted for mastication, the latter for imbibition of liquid food. Both types are, however, sometimes modified, and occasionally combined. Research Entomology
Ephedra (Ephedra vulgaris), also known as Ephedrine, Epitonin and Ma Huang, is an Asiatic plant of the order Gnetaceae found on sandy seashores in temperate climates of both hemispheres in China, Siberia and Japan. The plant has stamens and pistils on separate flowers, the staminate flowers occurring in catkins and a membranous perianth, pistillate flowers occurring terminal on axillary stalks within a two-leaved involucre. The fruit has two carpels with a single seed in each and is a succulentcone. The plant's branches are slender and erect with small leaves which are scale-like, articulated and joined at the base into a sheaf. The plant contains Ephedrine, a sympathetic nervestimulant resembling adrenaline and has antispasmodic properties. Research Ephedra
Mantodea is the praying mantis order of insects. They have three striking characteristics: a large triangular head with large eyes which can judge distance very accurately; a long prothorax to which the arms used for catching prey are attached; substantial spiky arms for catching prey. The animals are called praying mantis because when awaiting prey, they adopt a pose which resembles that of a person praying. Praying mantis vary in size with species (of which there are about 2500 distributed through over 400 genera) ranging from 15 mm to 250 mm long. Members of the order are to be found in warmer moderate climates, the sub-tropics and tropics and even in southern Europe. Most praying mantis lie in wait for their prey, and then strike at it with the enlarged front legs, then eating it alive. Desert dwelling species may actively hunt their prey, however. Often during mating the female rips the head off her partner, and eats it while still copulating with him, the thorax and abdomen continuing to be impelled by nerve endings. In this way the male
provides protein to his own offspring. However, a well-fed female will very often not eat her mate. Research Mantodea
The mole (Talpa) is a genus of burrowing mammal of the Talpidae family. The body is long and narrow, the tail short, the fore limbs placed far forward, while the hand is broad and powerful, and armed with five strong claws. They have no external ear, and the eyes are minute. Moles catch worms which they paralyse by damaging their nerve cord with a bite. These worms are then stored alive in the mole hills for future use when food is short. The typical and most widespread European mole is the common mole, but there are also the blind mole and Roman mole found in some parts of Europe. Research Mole
In biology, the term tissue is used for the substance of which the various parts of animal and plant bodies are composed. Thus, the substance of flesh or meat is known as muscular tissue, the substance of the brain and nerves is nerve tissue, that of bones is osseous tissue, that of the kidneys is renal tissue, that of glands in general is glandular tissue, and so on. Each of these particular tissues has its own characteristic cell structure. Research Tissue
Valerian is the Valeriana genus of plants of the family Valerianaceae having small fragrant flowers of white, purple or pink. The root was formerly used in medicine as a nerve sedative and antispasmodic. Common Valerian (Valeriana officinalis) is a perennialherb with a massive root system and a short rhizome, which bears angular, erect, furrowed, usually unbranched stems. It is native to Britain and Europe, where it grows on rough grassy and bushy places, often on damp soils. Research Valerian
Cameron Mitchell was an American actor. He was born in 1918 at Dallastown, Pennsylvania and died in 1994 of lung cancer. He is best remembered for playing the role of 'Buck Cannon' in the 1960's television series 'The High Chaparral' and also for starring in the 1956 western 'Tension at Table Rock' in which he played 'Fred Miller' the sheriff who had lost his nerve. Research Cameron Mitchell
The Probert Encyclopaedia was designed, edited and programed by
Matt and Leela Probert
Abbreviations
Research Bitter
