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,
    and unties our bone and is finished with the case,
    and turns to the next customer, forgetting our face
    or how we knelt at the yellow bulb with sighs
    like moth wings for a short while in a small place.
    Anne Sexton (1928–1974)

    ... 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.
    Tennessee Claflin (1846–1923)

    America is a model of force and freedom & moderation—with all the coarseness and rudeness of its people.
    George Gordon Noel Byron (1788–1824)