Giovanni Battista Porta (between 3— 15.10.1535—4.02.1615)—Italian scientist.
His physical research concerned optics, magnetism and crystallography. He gave a clear description of the camera obscura and improved it (1558) by using a converging lens. He proposed (1589) using the camera obscura for making drawings and for projecting them (the idea of the projection lantern). He used the principle of operation of the camera obscura in developing a theory of vision. He discussed the combination of a convex and a concave lens for observing distant and near objects. He performed (1601) an experiment to determine the quantity of steam into which a given quantity of water turns, and described (1606) the thermoscope and an experiment on raising water by the pressure of steam.
In 1560 he organised in Naples the first physical academy — the Academy of the Secrets of Nature