cylinder seal

(noun)

A small object adorned with carved images of animals, writing, or both, used to sign official documents.

Related Terms

Examples of cylinder seal in the following topics:

  • Sculpture in Mesopotamia

    • Sculptural forms include humans, animals, and cylinder seals with cuneiform writing and imagery in the round or as reliefs.
    • Animals, along with forms of writing, also appear on early cylinder seals, which were carved from stones and used to notarize documents.
    • Like the cylinder seal found in Queen Puabi's tomb, the figures in the Tell Asmar Hoard show hieratic scale.
    • An Uruk-period cylinder seal and stamped clay tablet featuring monstrous lions and lion-headed eagles, on display at the Louvre Museum.
    • Cylinder seal and stamped clay fragment from the tomb of Queen Puabi (c. 2600 BCE)

  • Art in the Second Millennium B.C.E.

    • The most common surviving forms of second millennium BCE Mesopotamian art are cylinder seals, relatively small free-standing figures, and reliefs of various sizes.

  • Cylinders and Quadric Surfaces

    • A cylinder (from Greek "roller" or "tumbler") is one of the most basic curvilinear geometric shapes.
    • The surface is formed by the points at a fixed distance from a given line segment, the axis of the cylinder.
    • The solid enclosed by this surface and by two planes perpendicular to the axis is also called a cylinder.
    • The surface area and the volume of a cylinder have been known since antiquity.
    • In common use, a cylinder is taken to mean a finite section of a right circular cylinder, i.e. the cylinder with the generating lines perpendicular to the bases, with its ends closed to form two circular surfaces.

  • Rotational Collisions

    • For example, take the case of an archer who decides to shoot an arrow of mass m1 at a stationary cylinder of mass m2 and radius r, lying on its side.
    • If the archer releases the arrow with a velocity v1i and the arrow hits the cylinder at its radial edge, what's the final momentum ?
    • Initially, the cylinder is stationary, so it has no momentum linearly or radially.
    • Once the arrow is released, it has a linear momentum p=mv1i and an angular component relative to the cylinders rotating axis, L=rp=rm1v1i.
    • The arrow hits the edge of the cylinder causing it to roll.

  • Complete Submersion

    • The buoyancy force on the cylinder is equal to the weight of the displaced fluid.
    • However (and this is the crucial point), the cylinder is entirely submerged, so the volume of the displaced fluid is just the volume of the cylinder (see ), and:
    • The volume of a cylinder is the area of its base multiplied by its height, or in our case :
    • $F_B = m_\mathrm{fl} g = V_\mathrm{cylinder} \rho g = (h_1 - h_2)\rho g A$.
    • The volume of the fluid displaced (b) is the same as the volume of the original cylinder (a).

  • Mammalian Systems and Protective Mechanisms

    • The respiratory tract is coated with mucus that is high in water to seal the tissues from direct contact with air.
    • The human trachea, a cylinder about 10-12cm long, 2cm in diameter found in front of the esophagus, extends from the larynx into the chest cavity.

  • Cylindrical Shells

    • The idea is that a "representative rectangle" (used in the most basic forms of integration, such as $\int x \,dx$) can be rotated about the axis of revolution, thus generating a hollow cylinder with infinitesimal volume.
    • Integration, as an accumulative process, can then calculate the integrated volume of a "family" of shells (a shell being the outer edge of a hollow cylinder), giving us the total volume.
    • By adding the volumes of all these infinitely thin cylinders, we can calculate the volume of the solid formed by the revolution.

  • Tight Junctions

    • Tight junctions serve as selectively permeable seals in our body's internal and external surfaces.
    • Tight junctions are virtually (but also partly selectively) impermeable seals that encircle cells and bind them together into leakproof sheets. 
    • Junctional adhesion molecules (JAMs) are immunoglobulin (antibody) proteins that help seal the intercellular space between two cells.
    • When fully formed, a tight junction is not one, long, continuous seal. 
    • Instead, it looks like a series of local seals joined together in a maze-like fashion. 

  • Government and Trade in the Achaemenid Empire

    • The Cyrus Cylinder is an ancient clay artifact, now broken into several fragments, that has been called the oldest-known charter of universal human rights and a symbol of his humanitarian rule.
    • The cylinder dates from the 6th century BCE and was discovered in the ruins of Babylon in Mesopotamia, what is now Iraq, in 1879.
    • In addition to describing the genealogy of Cyrus, the declaration in Akkadian cuneiform script on the cylinder is considered by many Biblical scholars as evidence of Cyrus’s policy of repatriation of the Jewish people following their captivity in Babylon.
    • The historical nature of the cylinder has been debated, with some scholars arguing that Cyrus did not make a specific decree, but rather that the cylinder articulated his general policy allowing exiles to return to their homelands and rebuild their temples.

  • Constant Pressure and Volume

    • An example would be to have a movable piston in a cylinder, so that the pressure inside the cylinder is always at atmospheric pressure, although it is isolated from the atmosphere.