armillary sphere, solstices, equinoxes, hipparchus, sextant, gnomon, cartouches, celestial mechanics, ancients, celestial sphere, astrolabe, stereoscopes, pendulums, mosaics, eratosthenes, astronomy, refracting telescope, foucault pendulum, engravings, lunette, armillary, sumerians, parabolic mirror, chessboards, camera obscura, hourglasses, obelisks, clocks, spectroscope, hieroglyphs, constellations, earthshine, celestial navigation, campanile, hyperbolic geometry, trivets, silverwork, broch, observatory, yantra, incunabula, theodolite, globes, spyglass, equinox, automata, sidereal, pyramids, polyhedrons, stained glass, geodesy, horology, sarcophaguses, phonographs, parallelograms, adzes, antiquity, clockmaker, tapestries, differential calculus, telescopes, celestial, quatrefoil, geoid, retroreflector, tipis, ogee, stelae, papyri, faience, harlow shapley, hieroglyphic, birchbark, theorems, filippo brunelleschi, analytic geometry, zoetrope, geometer, ruisdael, octagons, millefiori, tetrahedron, tesserae, dowsers, moonrise, compasses, carl friedrich gauss, lacemaking, babylonians, zithers, ugaritic, conic, steles, pythagoras, relativity theory, pictographs, jacquard loom, stereopticon, astronomical telescope, reredos, josef albers, potsherds, sundial, sculptures, windmills, calendars, furnaces, mills, lathes, looms, ovens, sculpture, statues, temples, altars, aqueducts, basilicas, carvings, dances, effigies, fireplaces