The Montgomery advertiser., 1901-12-29
MARCONIS WIRELESS SYSTEM How His Apparatus Enables Him to Telegraph
 Through the Air.

conf has done all his first work upon English soil His achievements in Italy attracted the attention of the English, and when, in 1896. he visited England on private business, some of hls friends ar ranged that he be invited to give an exhibition before the British authorities. The British gov4T1,nent furnished the ln- ventor facilities with which to give his
 exhibition, and he astonished them by sending wireless messages nine miles across the Bristol Channel.
 In transmitting these messages across the Bristol Channel Marconi used an or dinary ten-inch induction coil somewhat similar to the familiar shocking coil. but on larger scale. Connected to the ter minals of the secondary winding were two small spheres about one or two cen timeters apart. Between these spheres the spark passes and sets up the oscilla-
 ton necessary for the transmission of signals. When long distances are to be bridged, a vertical insulated conductor, suspended by means of a mast, Is at- tached to one sphere, and the other sphere Is connected with the earth If
 an ordinary telegraphic key connecting the battery with the coil be pressed. the current from the battery is allowed to actuate the induction coil, which charges the vertical conductor and discharges across the gap separating the two spheres. This discharge Is an oscillating one, and the insulated conductor becomes powerful radiator of electric waves. It may be easily seen how. by pressing the key for long or short intervals, 1t Is pos sible to emit long or short succession of waves which, when they influence the receiver, reproduce on 1t a long or short effect. according to their duration, In
 this way reproducing the Morse signals.
 The principal point in the Marconi re-
 ceiver is the sensitive tube or radio-con- ductor or, as it is generally termed, the
 coherer It consists of a small glass tube
 about four eentimeters in length into
 which two silver plugs are tightly fitted.
 4 small gap separate them, and In this gap na mixture of silver and nickel filings tis placedsn Under ordinary conditions the | resistan nae of this gap Is too high to al < low of any current passing from the To- cal cell or battery, but, under the influ- ence of electric waves, these filings 1n- stantly cohere and the tube becomes a | comparati lively good conductor. Connect ed to this tube is a cell and a relay. By the cohesion of the filings the current from the cell is allowed to pass through the tube and actuate the relay when once this is achieved 1t becomes very
 simple matter to make a bell ring or work an ordinary Morse inkwriter.
 One pecuIiarity of this cohesion or the filings un1er the influence of an electric waves is their power of remaining CO., | hered unless tapped or shaken up. Mar conf overcomes this difficulty by using | an automatic tapper or discoherer. It Is | similar to an electric bell, without the | bell This is so adjusted as to tap the | tube and shake the filings up, thus dls- | charging them and bringing them to their l normal condition. when they are agaln III I a state to receive another impulse. Ihls
 is worked by the relay and another local battery.