Bulb of Applied Force

In lithic analysis, a subdivision of archaeology, a bulb of applied force (also known as a bulb of percussion or simply bulb of force) is a defining characteristic of a lithic flake. When a flake is detached from its parent core, a portion of the Hertzian cone of force caused by the detachment blow is detached with it, leaving a distinctive bulb on the flake and a corresponding flake scar on the core. Bulbs of applied force may be distinctive, moderate, or diffuse, depending upon the force of the blow used to detach the flake, and upon the type of material used as a fabricator. Generally, the harder the material used as a fabricator, the more distinctive the bulb of applied force.


Famous quotes containing the words bulb, applied and/or force:

    ... until the shopkeeper plants his boot in our eyes,
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    ... in all cases of monstrosity at birth anaesthetics should be applied by doctors publicly appointed for that purpose... Every successive year would see fewer of the unfit born, and finally none. But, it may be urged, this is legalized infanticide. Assuredly it is; and it is urgently needed.
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    Mountains are to the rest of the body of the earth, what violent muscular action is to the body of man. The muscles and tendons of its anatomy are, in the mountain, brought out with force and convulsive energy, full of expression, passion, and strength.
    John Ruskin (1819–1900)