Waterbury Democrat., 1902-03-21
WIRELESS TELEGRApHY.
Discoverers and Practical inventors of the Various Systems of Aerial
 Communications.

 world, it is very Interesting to note the various stages by which this impor- tant method of communication has been reached and of the many sci entists to whom the world is indebted for the present efficiency of the sys- tenn, says the Washington Star.
 In 1850 Prof. Henry, of Washington, D. C., discovered that particles of car bon and steel were very sensitive to electrical discharges, and would act under electrical oscillations through the air (this being the forerunner of the sscoherer'), being an imperfect electrical contact. Prof. Hughes, of London, in 1880 also expeRimented with aerial telegraphy with some suc- cess.
 In 1882 Prof. Amos Emerson Dol bear, of Tufts college, Boston, Mass, applied for a basic or art patent for wireless telegraphy and telephony. After being held in the United States patent office for four years the com- missioner of patents demanded a working model of the system, claim ing that they could not understand it. as it was new art and the practical workings entirely unknown to them. Prof. Dolbear supplied the apparatus, making a practical demonstration of the same, and was granted patent Oe- tober 5, 1886, it being the first patent in the world of practical working wireless telegraph apparatus. Prof Dolbear worked his system in actual practice at that time between Blue hill and Boston light, a distance of over 13 miles. It is claimed that all who are using wireless telephony and telegraphy in the United States, there fore, necessarily infringe upon this basic patent, which is still in force.
 Prof. Heinrich Hertz in 1899 ex- plained the phenomena of electro etheric waves and established the fact, by demonstrating through the spark of his induction coil, that these waves were identical with the ordi- nary light waves, having the power of being reflected and refracted, thus solving the curious phenomena which had puzzled savants up to that time.
 Tn 1887 Sir William Preece expert. mented with wireless telegraphy in the English channel, and subsequently rendered able assistance to Sig. Mar conf.
 In 1890 Prof. E. Branley. of Paris, discovered the small sensitized tube called the 'tcoherer.' the connecting link of modern wireless telegraphy.
 Prof. Marconi has attracted world wide attention by the successful op- eration of his system, telegraphing 4I, s-I1 nIa 1,n{ Dover and Calais in March, 1899, and subsequently, erecting wireless sta- tions across the English and Irish coasts. Tn 1899 Prof. Marconi report ed the international yacht races, li- cense for this purpose having been granted by the owners of the Dolbear patent to the New York Herald, under whose auspices Prof. Marconi was then employed for this purpose.
 Prof Slaby, of Berlin, Germany, is also the inventor of a system which is now used in the German navy. and over which Emperor William is very enthusiastic. Prof Slaby claims that, in conjunction with Dr. Dietz, he made many experiments with ''spark teleg- raphy" before Marconi was ever known to the public.
 The various further inventions and improvements in wireless telegraphy in America have since been made by Profs. Collins, Shoemaker, Davis, Tes- la, Pickard. Fessenden and Ehret.
 On April l, 1901, Sig. Marconi surren- dered his United States patent, claim ing it imperative and too broad, in his claims citing that Prof. Popoff having IS months previously published a discovery and system similar to his, and therefore. after claiming his igno- rance of this fact Cat the time of filing same), he was granted a modified re- issue in June, 1901.
 Quite recently Prof. Harry Shoe maker, a rising young American in- ventor, has made many marked inn provements in wireless telegraphy, for which he has received 14 American patents. as well as patents in foreign countries. Prof. Shoemaker's patents mark an important epoch in the art of telegraphing without wires, covering, as they do, complete '.selective" sys- tenn, by which interference is entirely obviated. Prof. Shoemaker's tuning system is also very remarkable, it be- ing, it is claimed, perfectly adapted to practical and commercial uses.
 Prof. Nathan Stubblefield, of Ken lucky, who recently came upon the scene with a wireless telephone, and who is reported to have successfully talked from his residence to the court house, distance of about three blocks, is making progress on the lines of Dolbear's invention.
 The practical field for wireless telephony and telegraphy presents one of great promise and possibili- ties in the saving of lives as we'll as cheapening construction and com munications between distant points, and while it is not believed it will im- mediately displace telegraph and cable systems, any more than electricity has displaced that of gas, yet if it makes as much progress in the future as it has in the past two years the death knell of the poles, wires and cables and expensive messages has surely been sounded. The demands and uses of the wireless system are constantly increasing.
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