Futures Contract Specifications. Contract specifications for all North American-traded futures and commodities. Conveniently collected and displayed for easy reference, sorted by sector and market. Note that this specification list is updated manually and might contain inaccuracies. If you notice a problem, please contact TradingCharts.
Jul 24, 2014. J.J. Thomson used a cathode ray tube to discover the electron. Cathode ray tubes are vacuum tubes that contain two electrodes - one on each side. One of the electrodes (the cathode) fires electrons at the other (the anode) when voltage is added to the system. When Thomson fired up the tube, he saw a beam of light between the two electrodes. To figure out what they were, he applied a magnetic field and found out that the beam moved toward a positive charge and away from a negative charge.
Thomson first investigated the magnetic deflection of cathode rays. Cathode rays were produced in the side tube on the left of the apparatus and passed through the anode into the main bell jar, where they were deflected by a magnet. Thomson detected their path by the fluorescence on a squared screen in the jar.