An adit is a more or less horizontal opening, giving access to the shaft of a mine. It is made to slope gradually from the farthest point in the interior to the mouth, and by means of it the principal drainage is usually carried on. Research Adit
An alpenstock is a stout staff, iron-tipped, formerly used by mountain climbers, and since the mid-20th century largely replaced by the ice-axe. The names of ascended peaks were often branded onto its shaft. Research Alpenstock
In mines, a brattice is a partition of light wood or canvas which divides a shaft or underground roadway in two, and furnishes a means of conducting ventilation to the working face. Research Brattice
In mining, a stemple is a wooden cross-bar in a mine shaft serving both to prevent the earth from the sides of the shaft from falling in, and frequently formerly used as a ladder by the miners for climbing in and out of the shaft. Research Stemple
Underlay is a term applied to material laid under a carpet to protect it. In mining, an underlay is the inclination from the vertical or horizontal of a vein, fault, or lode. The term is also applied to a perpendicular shaft sunk to cut the lode at a required depth. Research Underlay
Feathers are the form which the dermal appendages assume in birds, agreeing in mode of development, but differing in form from hairs and scales. The feather consists of a stem, horny, round, strong, and hollow in the lower part, called the quill, and in the upper part, called the shaft, filled with pith. On each side of the shaft is a web composed of a series of regularly-arranged fibres called barbs. The barbs and shaft constitute the vane. On the edges of the barbs are set the barbules, which interlock with those of adjacent barbs, and thus give strength to the vane.
Feathers are generally divided into two kinds, quill feathers in the wing or tail, and plumes or clothing feathers generally diffused. The feathers of birds are periodically changed, generally once, but in some species twice a year. This is called moulting. When feathers have reached their full growth they become dry, and only the tube, or the vascular substance which it contains, continues to absorb moisture or fat. When, therefore, part of a feather is cut off, it does not grow out again;
and a bird whose wings have been clipped remains in that situation until the next moulting season, when the old stumps are shed and new feathers grow out. If, however, the stumps are pulled out sooner the feathers will be renewed in a few weeks or even days.
The feather is a very strong formation, not readily damaged, the arch of the shaft resisting pressure, while the web and fine fibres yield without suffering. Being a bad conductor of heat it preserves the high temperature of the bird, while it is so light as to be easily carried in flight. It is rendered almost impervious to wet by the oily fluid which most birds secrete at the base of the tail. Feathers traditionally formed a considerable article of commerce, particularly those of the ostrich, heron, swan, peacock, goose, etc, for plumes, ornaments, filling of beds, pens, etc. Research Feather
The Ladybird Spider is the rarest of Britain's 450 species of spider. It is so named on account of the adult male having a scarlet back with four black spots, resembling a ladybird. The head is black, the legs are black with white stripes. The Ladybird Spider lives in heather heathland where it builds a web across a vertical shaft in which it lives. Approaching beetles triggertripwires or walk over the web and the spider pounces, biting them with quick acting toxin and then eats its prey. The Ladybird Spider was thought to be extinct in the 1920's, but was rediscovered in the 1980's in the south of England. Research Ladybird Spider
The compact bone tissue serves as the outer shell of the bone and serves to protect the inner core of spongy bone (trebiculae, or substantia spongiosa). The compact bone shell is particularly thick in the middle of the shaft in long bones in order to protect the bone against bending. The compact bone is covered by the periosteum. Research Compact Bone
The diaphysis, or shaft, of a long bone features a shell of compact bone surrounded by the periosteum, a cartilaginous membrane which contains the blood vessels which provide nutrients to the bone. The diaphysis is separated from the epiphyses of the bone by the epiphyseal line. Research Diaphysis
The Probert Encyclopaedia was designed, edited and programed by
Matt and Leela Probert
Abbreviations
Research Adit
