. Electrical world. case if the effect had been due to diffraction. On re-reading M. Blondels paper I see, however, that there isone point in which our ideas possibly do differ, i. e., on the effect ofthe earth. This question is rather complicated and I intend discussing it ina separate article. For the present I will give an actual practicalillustration of its use which I think will indicate that there is some-thing more required besides actually grounding the conductor. Inthe experiments above referred to a station was erected on theshore of an island at the point S, the island having roughl
. Electrical world. case if the effect had been due to diffraction. On re-reading M. Blondels paper I see, however, that there isone point in which our ideas possibly do differ, i. e., on the effect ofthe earth. This question is rather complicated and I intend discussing it ina separate article. For the present I will give an actual practicalillustration of its use which I think will indicate that there is some-thing more required besides actually grounding the conductor. Inthe experiments above referred to a station was erected on theshore of an island at the point S, the island having roughly theshape shown in the accompanying figure. The island was formedof a mass of rock with slight patches of grass but without any soilupon it. The antennae was grounded by a plate inserted in the waterso that the resistance as actually measured between the antennaeand ground was only a few ohms. A second set of apparatus was placed upon a tug boat having a50-foot mast. When the tug boat was in the position A signals. WIRELESS TELEGRAPH EXPERIMENTS. were received as far as the boat could go on the opposite side of thebay, I. e., about 15 miles. On the tug boat passing around to thepoint B, while a message was being received on the boat the messagewas cut off in the middle of a word, absolutely, sharply and de-cisively, and communication was established equally as sharply onthe boat reaching the same position when moving in the oppositedirection. At all points beyond B in the direction of C it was im-possible to obtain any communication. A wave chute was then laidover the surface of the island, consisting of a galvanized iron wirespread out in a fan shape and grounded in the water as shown at W. As soon as this wave chute was constructed, communication wasimmediately established when the tug boat was in the position C,and on the tug boat moving off in that direction, a distance of 14miles, the intensity appeared to be, if anything, stronger than in thedirection A. Bearing in mind,
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectelectri, bookyear1883
