Cranes may be divided into two main classes - revolving and non-revolving.
In revolving cranes ease of slewing can be greatly increased by the use of a live ring of conical rollers.
18 shows a modern design of crane intended to command the maximum of yard space, and having some of the characteristics both of the Goliath and of the revolving jib crane, and fig.
BINARY SYSTEM, in astronomy, a system composed of two stars revolving around each other under the influence of their mutual attraction.
4 is a diagram of a fixed hand revolving jib crane, of moderate size, as used in railway goods yards Fixed and similar places.
The hydraulic lifting cylinders are placed inside the revolving steel mast or post, and the cabin for the driver FIG.
As types of non-revolving cranes, fig.
The mouth of the bottle is ground by a revolving iron cone, or mandrel, fed with sand and water and driven by steam.
19) consists of a revolving table carrying five or six moulds.
On the 8th of March about 1 p.m., the "Merrimac," commanded by Commodore Franklin Buchanan (1795-1871), steamed down the Elizabeth accompanied by two one-gun gun-boats, to engage the wooden fleet of the Federals, consisting of the frigate "Congress," 50 guns, and the sloop "Cumberland," 30 guns, both sailing vessels, anchored off Newport News, and 1 For the idea of the low free-board and the revolving turret Ericsson was indebted to Theodore R.
Wheels creak on their axles as the cogs engage one another and the revolving pulleys whirr with the rapidity of their movement, but a neighboring wheel is as quiet and motionless as though it were prepared to remain so for a hundred years; but the moment comes when the lever catches it and obeying the impulse that wheel begins to creak and joins in the common motion the result and aim of which are beyond its ken.
High, with a revolving white light visible 18 m.
The revolving part is made with two side frames of cast iron or steel plates, and to these the lifting gear is attached.
Load is suspended from the crane jib; this jib is attached at the lower end to the side frames, and the upper end is supported by tierods, connected to the framework, the whole revolving together.
The principal component parts of a traveller are the main cross girders forming the revolving bridge, the two end carriages on which the bridge rests, the cranes.
In the same way the arrangements finally elaborated by Lodge and Muirhead consisted of a direct coupled antenna and nearly closed condenser circuit, and a similar receiving circuit containing as a detector the steel wheel revolving on oily mercury which actuated a siphon recorder writing signals on paper tape.
The surface formed by revolving the catenary about its directrix is named the alysseide.
The kilns are made with either fixed or revolving retorts.
The "Monitor" had the advantage of being able to out-manoeuvre her heavier and more unwieldy adversary; but the revolving turret made firing difficult and communications were none too good with the pilot house, the position of which on the forward deck lessened the range of the two turret-guns.
He first undertook a preliminary inquiry into the principles upon which flight depends, and established at Allegheny a huge "whirling table," the revolving arm of which could be driven by a steamengine at any circumferential speed up to 70 m.
But in other cases the encrusted star settles in that portion of the revolving vortex which has a velocity equivalent to its own, and so continues to revolve in the vortex, wrapped in its own firmament.
The nodules from the "blue earth" have to be freed from matrix and divested of their opaque crust, which can be done in revolving barrels containing sand and water.
In the system devised by Mr Louis Brennaxi the cars run on a single rail laid on the ground, their stability being maintained by a heavy gyrostat revolving at great speed in a vacuum.
The revolving masses are truly balanced by balance weights placed between ' the spokes of the wheels, or sometimes by prolonging the crank-webs and forming the prolongation into balance weights.
It is also the custom to balance a proportion of the reciprocating masses by balance weights placed between the spokes of the wheels, and the actual balance weight seen in a driving-wheel is the resultant of the separate weights required for the balancing of the revolving parts and the reciprocating parts.
When the four cranks are placed with two pairs at 180°, the pairs being at 90°, the forces are balanced without the introduction of a hammer-blow, but there remain large unbalanced couples, which if balanced by means of revolving weights in the wheels again reintroduce the hammerblow, and if left unbalanced tend to make the engine oscillate in a horizontal plane at high speed.
We have thus grounds for believing that the original nebula will separate into a series of rings all revolving in the same direction with a central nebulous mass in the interior.
Among the more remarkable phenomena of the hotter seas of Asia must be noticed the revolving storms or cyclones, which are of frequent occurrence in the hot months in the Indian Ocean and China Sea, in which last they are known under the name of typhoon.
It consists essentially of a series of circular notched disks, the so-called saws, revolving between the interstices of an iron bed upon which the cotton is placed: the teeth of the " saws " catch the lint and pull it off from the seeds, then a revolving brush removes the detached lint from the saws, and creates sufficient draught to carry the lint out of the machine to some distance.
After the seed of Upland cotton has been passed through a fine gin, which takes off the short lint or linters left upon it by the farmer, it is passed through what is called a sheller, consisting of a revolving cylinder, armed with numerous knives, which cut the seed in two and force the kernels or meats from the shells.
In this he showed that a homogeneous fluid mass revolving uniformly round an axis under the action of gravity ought to assume the form of an ellipsoid of revolution.
Orbita, a track, orbis, a wheel), in astronomy, the path of any body, and especially of a heavenly body, revolving round an attracting centre.
This is defined as the speed of revolution of the fictitious body already described, revolving with a uniform angular motion and the same periodic time as the planet.
QUERN, the primitive form of hand-mill for grinding corn, consisting of two flat circular stones; the lower stone, often shaped with a rim; has a wooden or metal pin in the centre which passes through a hole in the upper stone; the worker pours the grain through the hole with one hand, revolving the upper stone with the other by means of a peg fixed to one side.
Hence processes have been patented in which the objects to be plated are suspended in revolving drums between the anodes, the rotation of the drum causing the constant renewal of surfaces and affording a burnishing action at the same time.
There are strong reasons for believing that magnetism is a phenomenon involving rotation, and as early as 1876 Rowland, carrying out an experiment which had been proposed by Maxwell, showed that a revolving electric charge produced the same magnetic effects as a current.
The effect of the field upon the speed of the revolving electrons, and therefore upon the moments of the equivalent magnets, is necessarily a very small one.
If the structure of the molecule is so perfectly symmetrical that, in the absence of any external field, the resultant magnetic moment of the circulating electrons is zero, then the application of a field, by accelerating the right-handed (negative) revolutions, and retarding those which are left-handed, will induce in the substance a resultant magnetization opposite in direction to the field itself; a body composed of such symmetrical molecules is therefore diamagnetic. If however the structure of the molecule is such that the electrons revolving around its atoms do not exactly cancel one another's effects, the molecule constitutes a little magnet, which under the influence of an external field will tend to set itself with its axis parallel to the field.
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.
Earthy matter and other matter precipitated and fallen on the copper double bottom may be dislodged by a slowly revolving scraper - say every twelve hours - and ejected through the bottom discharge cock; and thus the heating surface of the copper bottom will be kept in full efficiency.
They are weighed and then dumped into a washing machine, consisting of a large horizontal cage, submerged in water, in which revolves a horizontal shaft carrying arms. The arms are set in a spiral form, so that in revolving they not only stir the roots, causing them to rub against each other, but also force them forward from the receiving end,of the cage to the other end.
Sometimes the cells are erected in a circle, so that the spout below the slicing machine revolving above them with a corresponding radius can discharge the slices into the centre of any of the cells.
Granulated sugar, so called, is made by passing the crystals, after leaving the centrifugals, through a large and slightly inclined revolving cylinder with a smaller one inside heated by steam.
The roasting is most simply effected by spreading it on heated slabs, on which it is constantly turned, or a roasting machine is used, consisting of a revolving drum in which the tobacco is rotated, gradually passing from one end to the other, and all the time under the influence of a current of heated air.
The coulter is a knife or revolving disk which is fixed so that its point clears the point of the share.
In the United States a revolving furnace is used which is quite continuous in action.
Accordingly, the vessel was built so low in the water that the waves glided easily over its deck except at the middle, where was constructed a revolving turret 1 for the guns, and though the vessel's iron armour had a thickness of 1 in.
Between the customs house and the railway terminus is the mouth of a small river, the Chiveve, crossed by a steel bridge, the centre span revolving and giving two passages each of 40 ft.