In the mid-nineteenth century, magnetic theories penetrated other recognized medical practices in Argentina in order to rationalize their procedures, in a culture that accepted and validated magnetism as a positive science. At the start of the twentieth century, mesmerists created a society, published books and journals, and carried out a large welfare programme; there were public lectures, and magnetic treatment for spiritualists and the general public, emphasizing the therapeutic properties of mesmerism. Magnetologists/mesmerists measured vital radiation and built devices using sensitive objects as 'physical' evidence of it. There was an interest in acquiring and using artefacts to measure human radiation useful in medicine. Magnetic practices survived until the end of the 1920s, when they lost importance.
Keywords: Fluids; Ovidio Rebaudi; magnetism; medicine; mesmerism; spiritism; vital radiation.