lever

Definitions

  • Archeological explorations revealed that the colonists enjoyed archery. The iron lever shown, known as a “goat’s foot,” was used for setting the string of a light hunting crossbow. It was found 4 miles from Jamestown. showing the use of a “goat’s foot” from _Weapons, A Pictorial History_ by Edwin Tunis
    Archeological explorations revealed that the colonists enjoyed archery. The iron lever shown, known as a “goat’s foot,” was used for setting the string of a light hunting crossbow. It was found 4 miles from Jamestown. showing the use of a “goat’s foot” from _Weapons, A Pictorial History_ by Edwin Tunis
  • WordNet 3.6
    • v lever to move or force, especially in an effort to get something open "The burglar jimmied the lock": "Raccoons managed to pry the lid off the garbage pail"
    • n lever a rigid bar pivoted about a fulcrum
    • n lever a flat metal tumbler in a lever lock
    • n lever a simple machine that gives a mechanical advantage when given a fulcrum
    • ***

Additional illustrations & photos:

Double Lever Key Double Lever Key

Webster's Revised Unabridged Dictionary
  • Interesting fact: An artificial hand , with fingers moved by cogwheels and levers, was designed in 1551 by Frenchman Ambroise Paré. It worked so well that a handless cavalryman was able to grasp the reins of his horse.
    • Lever (Mach) A bar, as a capstan bar, applied to a rotatory piece to turn it.
    • Lever (Mech) A rigid piece which is capable of turning about one point, or axis (the fulcrum), and in which are two or more other points where forces are applied; -- used for transmitting and modifying force and motion. Specif., a bar of metal, wood, or other rigid substance, used to exert a pressure, or sustain a weight, at one point of its length, by receiving a force or power at a second, and turning at a third on a fixed point called a fulcrum. It is usually named as the first of the six mechanical powers, and is of three kinds, according as either the fulcrum F, the weight W, or the power P, respectively, is situated between the other two, as in the figures.
    • Lever (Mach) An arm on a rock shaft, to give motion to the shaft or to obtain motion from it.
    • a Lever lē"vẽr More agreeable; more pleasing.
    • adv Lever Rather. "For lever had I die than see his deadly face."
    • ***
Century Dictionary and Cyclopedia
    • n lever A simple machine, consisting of a bar or rigid piece of any shape, acted upon at different points by two forces which severally tend to rotate it in opposite directions about a fixed axis. The bearing of this axis is called the fulcrum; of the two forces, one, conceived as something to be balanced or overcome, is termed the resistance, load, or weight, while the other, conceived as voluntarily applied, is termed the power. These are understood to act in the plane of rotation, and each perpendicularly to the line joining the point of its application to the fixed axis. The lengths of these two lines are termed the arms of the lever. If the load is ten times as great as the power, but the power is ten times as far from the fulcrum as the load is from the fulcrum—or, generally, if the two forces are inversely as their respective arms—then the lever is in equilibrium. This principle, beautifully demonstrated by Archimedes, was adopted by Lagrange as one of the two fundamental principles of statics, the other being the principle of the inclined plane. A lever is said to be of the first, second, or third kind, according as of the three points—the fulcrum, the point of application of the load, and that of the power—the first, second, or third is between the other two. But this distinction is insignificant; and when these three points are the vertices of a triangle, and the lever is not in the form of a bar, which often happens, the distinction becomes confused. Among the innumerable examples of levers may be mentioned the steelyard, the crowbar, oars, and the bones of the human limbs.
    • n lever In special uses— In surgery, an instrument for applying power, as one of the arms of an obstetrical forceps, used in delivery as a tractor; the vectis.
    • n lever In dentistry, an instrument used in extracting the stumps of teeth.
    • n lever In a steam-engine, a bar used to control by hand the movement of the engine in starting or reversing it; a starting-bar.
    • n lever In firearms, in some forms of breech-loaders, the piece by which the gun is opened or closed, as in the Douglas, Henry, and Maynard rifles. It may be a top, side, or under lever.
    • n lever One of the chief supporters of the roof-timber of a house, being itself not a prop, but a part of the framework.
    • n lever The lower movable board of a barn-door.
    • n lever The first row of a fishing-net.
    • n lever Generally, a rod or bar.
    • lever To act upon, as raising, lowering, etc., with a lever.
    • lever An obsolete comparative of lief.
    • ***
Chambers's Twentieth Century Dictionary
    • n Lever lē′vėr a bar of metal or other substance turning on a support called the fulcrum or prop, for imparting pressure or motion from a source of power to a resistance—of three kinds, according to the relative positions of the power, weight, and fulcrum:
    • adv Lever lē′vėr an obsolete comp. of lief.
    • n Lever lē′vėr (fig.) anything which exerts influence: any one of various tools on the principle defined above—in surgery, dentistry, &c.: a removable rod or bar inserted in a machine, to be operated by hand leverage
    • ***

Quotations

  • Napoleon Bonaparte
    Napoleon%20Bonaparte
    “Men are Moved by two levers only: fear and self interest”
  • Thomas J. Watson
    Thomas%20J.%20Watson
    “Don't make friends who are comfortable to be with. Make friends who will force you to lever yourself up.”
  • Daniel Webster
    Daniel%20Webster
    “Mind is the great lever of all things.”
  • Napoleon Bonaparte
    Napoleon%20Bonaparte
    “There are two levers for moving men -- interest and fear.”
  • Archimedes
    Archimedes
    “Give me a lever long enough, and a prop strong enough, I can single-handed move the world.”
  • Margaret Thatcher
    Margaret%20Thatcher
    “I shan't be pulling the levers there but I shall be a very good back-seat driver.”

Etymology

Webster's Revised Unabridged Dictionary
OE. levour, OF. leveor, prop., a lifter, fr. F. lever, to raise, L. levare,; akin to levis, light in weight, E. levity, and perh. to E. light, not heavy: cf. F. levier,. Cf. Alleviate Elevate Leaven Legerdemain Levee Levy (n.)
Chambers's Twentieth Century Dictionary
Fr. levierlever—L. levāre, to raise.

Usage

In literature:

Superior Gold London-made Patent Levers, 17, 15, and 12 guineas.
"Notes and Queries, Number 214, December 3, 1853" by Various
Bud had pulled the copper lever toward him, and, in spite of its size and weight, it moved easily in what appeared to be a slot in the rock.
"The Boy Ranchers in Camp" by Willard F. Baker
The levers, 14 inches long, project from the frame and strike the floor much as a flail would.
"Agricultural Implements and Machines in the Collection of the National Museum of History and Technology" by John T. Schlebecker
He flipped a lever in the back of the camera.
"Starman's Quest" by Robert Silverberg
Superior Gold London-made Patent Levers, 17, 15, and 12 guineas.
"Notes and Queries, No. 209, October 29 1853" by Various
Superior Gold London-made Patent Levers, 17, 15, and 12 guineas.
"Notes and Queries, Number 219, January 7, 1854" by Various
When Droop had completed his lecture, Phoebe found that she understood the uses of three of the levers.
"The Panchronicon" by Harold Steele Mackaye
Levers K and L fulcrumed at J and J are connected to the valve spindles by auxiliary levers.
"Steam Turbines" by Hubert E. Collins
The throttle lever is a simple arrangement readily understood from the drawings.
"The 'Pioneer': Light Passenger Locomotive of 1851" by John H. White
Superior Gold London-made Patent Levers, 17, 15, and 12 guineas.
"Notes and Queries, Number 231, April 1, 1854" by Various
The left-hand lever moved only backwards and forwards; it controlled the elevator and directed the machine upwards or downwards.
"The War in the Air; Vol. 1" by Walter Raleigh
Ralph had swung the air lever or there would have been a catastrophe.
"Ralph on the Engine" by Allen Chapman
Superior Gold London-made Patent Levers, 17, 15, and 12 guineas.
"Notes and Queries, Number 223, February 4, 1854" by Various
Superior Gold London-made Patent Levers, 17, 15, and 12 guineas.
"Notes and Queries, Number 192, July 2, 1853" by Various
Superior Gold London-made Patent Levers, 17, 15, and 12 guineas.
"Notes and Queries, Number 193, July 9, 1853" by Various
Superior Gold London-made Patent Levers, 17, 15, and 12 guineas.
"Notes and Queries, Number 194, July 16, 1853" by Various
Superior Gold London-made Patent Levers, 17, 15, and 12 guineas.
"Notes and Queries, Number 195, July 23, 1853" by Various
Superior Gold London-made Patent Levers, 17, 15, and 12 guineas.
"Notes and Queries, Number 217, December 24, 1853" by Various
He manipulated its levers and wheels with an expert's assurance.
"Astounding Stories of Super-Science January 1931" by Various
Its iron hands pulled at levers.
"Astounding Stories, April, 1931" by Various
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In poetry:

Down my cheek ran tears in fever,
While with axe its stem I cut;
Soon it fell, and I with lever
Roll’d it straight to Emma’s hut.
"The Violet-Gatherer (From The Danish Of Oehlenslaeger)" by George Borrow
I saw from windows, as if hung in air,
'Mid handles gleaming white,
Pointsmen that clutched and drew the levers there,
And set the points aright.
"Bannockburn" by Alexander Anderson
Help came but slowly; surely no man yet
Put lever to the heavy world with less:
What need of help? He knew how types were set,
He had a dauntless spirit, and a press.
"To W.L. Garrison" by James Russell Lowell
The boat-express is waiting your command!
You will find the Mauritania at the quay,
Till her captain turns the lever 'neath his hand,
And the monstrous nine-decked city goes to sea.
"The Secret of the Machinery" by Rudyard Kipling
"I took one look again, then sung out to my mate,
'We can never draw up, we have seen it too late.'
When, sudden and swift, like the change in a dream,
Nottman drew back the lever, and flung on the steam.
"Nottman" by Alexander Anderson
Worse iron is waiting. Power-lift kneels
Levers awake imprisoned deadweight,
Shackle-pins bedded in cast-iron cow-shit.
The blind and vibrating condemned obedience
Of iron to the cruelty of iron,
Wheels screeched out of their night-locks -
"Tractor" by Ted Hughes

In news:

Lever House Art Colllection, New York.
Learning how to manipulate the three basic levers of wealth creation.
Barnes Buster Bullets For Handguns (And Lever -Actions).
Right-to-Know Law Gives India's Poor a Lever .
Al Lever and the American College of Chest Physicians offer exhibitors clinical resource centers as alternatives to traditional booths.
New Schlage Lever Lock with Built-in Alarm.
Institutional line of lever designs retain existing functionality, adds aesthetically pleasing features.
With levers, ancient Egyptians raised huge obelisks and the people of Rapa Nui raised massive moai.
Explore how levers work in this online activity.
Objective To investigate how levers can be used to lift objects.
Copy of "Lever Loads" student handout (PDF or HTML).
Bowman, who farms 2,000 acres, illustrates what agriculture and political experts such as Iowa State University political scientist Steffen Schmidt say is a potential lever to sway on-the-fence voters in Iowa.
Viewing Ideas for the NOVA program Secrets of Lost Empires II— Pharaoh 's Obelisk: The ancient building methods shown in the programs depend on the use of simple machines, including levers, ramps, pulleys, and wheels.
I know you're hoping that one night he'll take a big slurp off his brewski, pull that lever into its most supine setting, and put those reclining sofas (ugh.
Two of the civilians aboard a US submarine that collided with a Japanese trawler -- one of whom pulled levers to surface the sub -- denied that they distracted the crew and contributed to the tragedy.
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In science:

We showed previously that the velocity c of the interface is a function of the total shear stress σ only, and that c = 0 when σ = σ∗ [8, 10] which via the lever rule corresponds to a unique stable interface position r∗ .
Timescales in shear banding of wormlike micelles
With AMANDA-II data taken in 2000, we gain improved sensitivity over the entire visible sky, and most critically, to events near the horizon since the detector has double the number of PMTs and a larger lever arm in the horizontal dimension.
Physics and Operation of the AMANDA-II High Energy Neutrino Telescope
The magnetic lever arm (defined as the ratio rA /r0 between the Alfv`en and footpoint radii) is in the range 3.5 - 4.6 (with an accuracy of 20 - 25 %), or, alternatively, the ejection index ξ = d ln( ˙Macc )/dr is in the range 0.025 - 0.046 (with similar uncertainties).
Jet rotation: launching region, angular momentum balance and magnetic properties in the bipolar outflow from RW Aur
WFPC2 photometric zero-points that reduce the ‘lever arm’ of corrections necessary to account for non-linearity and CTE anomalies in WFPC2.
Cepheid Distances to SNe Ia Host Galaxies based on a Revised Photometric Zero-Point of the HST-WFPC2 and New P-L Relations and Metallicity Corrections
Note that a qualitative observation of scaling violations of structure functions alone does not yet prove Asymptotic Freedom - such a conclusion requires a large lever arm in Q2 and a precise study of the functional form of observed scaling violations, as e.g. the logarithmic slopes, ∂F2 (x, Q2 )/∂ lnQ2 .
Experimental Tests of Asymptotic Freedom
The long lever arm and complementarity provided by such an analysis has previously led to a significant tightening of the constraints on the shape and the amplitude of the power spectrum of primordial density fluctuations.
Probing Neutrino low energy and mass scales
This lever arm may provide significant systematic checks of hydrodynamic flow and jet quenching.
Phases of QCD: Summary of the Rutgers Long Range Plan Town Meeting
This is consistent with the model predictions, although the precision of the data is limited experimentally by the small lever-arm in W .
Diffraction and Vector Mesons Working Group Summary
The relatively good ability of NTs to reconstruct spectra even for a limited energy resolution of ∆(log10E ∼ 0.3) is due to the wide energy range over which they operate (between about 100 GeV to EeV energies): detected events provides a long lever arm for spectral reconstruction.
Rapporteur Summary of Sessions HE 2.2-2.4 and OG 2.5-2.7
In this microscope the scanning was done with a lever mechanism, with the sample attached to the bottom of the lever, and mechanical motors operating the other end of the lever at room temperature at the top of the dewar.
Probing the order parameter symmetry in the cuprate high temperature superconductors by SQUID microscopy
Turning to the variation of XS with z1 , the predicted value of XS is maximal at z1 = 0 (with a value of 1.185 for our reference model C), and slowly declines with z1 : thus lower z1 is better both to maximise lever-arm in our speedtrap, and to minimise curvature uncertainty.
A cosmic speed-trap: a gravity-independent test of cosmic acceleration using baryon acoustic oscillations
The challenge remains, therefore, to describe explain exactly what type of non-stationarity must be present to make such improvement possible and whether this understanding may be levered to design methods which yield higher improvements in the face of non-stationarity.
Two Projection Pursuit Algorithms for Machine Learning under Non-Stationarity
Bjorken scaling violation at high x, measured using the long lever arm provided by HERA.
Summary of Lepton Photon 2011
Response 8 was obtained by clicking on lever in Response 7, and selecting What-is-it from the pop-up menu.
Automatic Generation of Technical Documentation
The final stage is converting the SPL into a surface form, i.e., actual text; the output of the surface realisation module is It is a black locking lever.
Automatic Generation of Technical Documentation
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