The first act of the female after oviposition is to wrap her eggs in a casing of silk commonly called the cocoon.
Casing, having a collar to fit water-tight on the bevel shoulder, is inserted.
Four strings of iron casing are usually employed, having the following diameters: to in., 84 in., 64 in.
And 5 in., the lengths of tube forming the casing being screwed together.
The principle of this system consists essentially in the use of rotating hollow drilling rods or casing, to which is attached the drilling-bit and through which a continuous stream of water, under a pressure of 40 to loo lb.
The device employed for this purpose is known as the water-packer, and consists in its simplest form of an india-rubber ring, which is applied between the tubing and the well-casing, so that upon compression it makes a tight joint.
Casing descending freely, which obviously could not be accomplished with an ordinary bit introduced through the casing.
Some of the rubber having been placed in the annular space between the inner cylinder and the outer casing, the former is made to revolve; and the continued kneading action to which the rubber is subjected works it into a solid mass, something like a gigantic sausage.
The inner cylinder is generally placed somewhat excentrically in the outer casing, in order to render the kneading more perfect than would otherwise be the case.
The typical mine fan consists of a shaft upon which are mounted a number of vanes enclosed in a casing; the air entering a central side inlet is caught up by the revolving vanes and thrown out at the periphery by the centrifugal force thus generated.
An outer cast-iron casing, which forms a steam jacket, and is fitted with a cylindrical curb or breast above the bottom.
By means of a travelling crane the casing is placed within an iron drum, to which it is secured, and is then brought under an overhead vacuum pan, from which the cells are filled with massecuite.
After cooling, the casing is lifted out of the drum by a crane, assisted by compressed air, and is then conveyed by a travelling crane to a vertical centrifugal, inside of which it is made fast.
When this is done, the casing is hoisted out of the centrifugal and the vertical plates and the slabs of sugar are extracted.
Of these methods one of the chief is the plan of tubbing, or lining the excavation with an impermeable casing of wood or iron, generally the latter, built up in segments forming rings, which are piled upon each other throughout the whole depth of the water-bearing strata.
The lower quadrant of the casing is enlarged spirally, so as to leave a narrow rectangular opening at the bottom, through which the air is discharged into a chimney of gradually increasing section carried to a height of about 25 ft.
By the use of the spiral guide casing and the chimney the velocity of the effluent air is gradually FIG.
13, is an example of another class of centrifugal ventilator, in which a close casing is not used, the air exhausted being discharged from the circumference directly into the atmosphere.
This replaced the propeller of the ship whose engines were to be tested, and the outer casing was held from turning by a suitable arrangement of levers carried to weighing apparatus conveniently disposed on the wharf.
Sluices were arranged to slide be tween the wheel and casing, and by their means the range of action could be varied from 300 H.P. at 120 revs.
99, p. 167), using Froude's turbine to obtain the highly resisting spiral vortices, and arranging passages in the casing for the entry of water at the hub of the wheel and its exit at the circumference.
The casing is held from turning by weights hanging on an attached arm.
Lating the water are connected to the casing, so that any tilting automatically regulates the flow, and therefore the thickness of the film in the vortex.
The torque required to hold the casing still against the action of the disk measures the torque exerted by the shaft to which the disk is keyed.
Not only was he the first discoverer of the rotifers, but he showed "how wonderfully nature has provided for the preservation of their species," by their tolerance of the drying-up of the water they inhabit, and the resistance afforded to the evaporation of the fluids of their bodies by the impermeability of the casing in which they then become enclosed.
The material is placed in a perforated cage or "basket," which is enclosed in an outer casing, and when the cage is rapidly rotated by suitable gearing, the liquid portions are forced out into the external casing.
In some soils foundations may be obtained by the device of building a masonry casing like that of a well and excavating the soil inside; the casing gradually sinks and the masonry is continued at the surface.
The reel to which the raw silk is led consists of a light six-armed frame, enclosed within a wooden casing having a glass frame in front, the enclosure being heated with steam-pipes.
5) are reflected by a mirror B down the centre of the conical casing which contains the upper optical system and is attached to the top of the mast.
Built in brick, it was found necessary to give a more monumental appearance to the walls by a casing of stucco, which remains in fair preservation to the present day.
The decoration of the interior consists of the casing of the walls with marble with enriched borders, and (about 20 ft.
The former are used principally as casing, walls, pillars or other supporting parts of the structure, and includes ordinary red or yellow bricks, clay-slate, granite and most building stones; the latter are reserved for the parts immediately in contact with the fuel and flame, such as the lining of the fire-place, the arches, roof and flues, the lower part if not the whole of the chimney lining in reverberatory furnaces, and the whole of the internal walls of blast furnaces.
For the latter purpose, however, lime is generally used; but as this substance has only small stability, it is usually bedded in a casing of firebrick.
Puddling furnaces are usually entirely cased with iron plates, and blast furnaces with hoops round each course of the stack, or in those of thinner constructions the firebrick work is entirely enclosed in a wrought iron casing or jacket.
Such producers, frequently strengthened by a wrought iron casing, are even now used to a great extent.
L is the producer-shaft, with an iron casing B and peep holes B 1 to B4, passing through the brick lining M.
In the brake shown, the cone I is pressed against a corresponding recess in the ratchetwheel J, which latter turns loosely in the casing and is provided with a pawl not shown in the figure; this pawl allows freedom of motion when the load is being raised.
- A light and carefully balanced drum with its axis horizontal is enclosed within a cylindrical casing, and rotates freely in bearings formed in the ends of the casing.
The casing is fixed in supports on the top of a strong frame, which also carries a small platform machine of ordinary construction on which the goods to be weighed are placed.
At each end of the drum casing is attached a vertical spiral spring, and by the extension of these springs the weighing of the goods is effected.
There are also two vertical racks, one at each end of the casing, in connexion with - the two springs, and these actuate pinions on the axle of the drum and cause it to revolve as the springs extend.
By this means the zero of the scale on the drum can be adjusted to the fixed index on the casing when there are no goods on the platform.