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. Scientific American Volume 86 Number 14 (April 1902) . eing 110 volts V A. You must begoverned by the heating of your coil. Fse onlyso much current as will not heat the coil sothat the insulation burns. That would destroythe coil. A. In making a permanent magnetof tool steel, shall I first soften the steel beforemagnetizing it. or should it be hardened at theends. A. Harden the bar at the ends glasshard. (8580) H. N. B. asks: 1. Can the simple induction coil described iu lOx peri-mental Science be used to transmit messagesby wireless telegraphy V If so, how far wouldit be possible to transmi

. Scientific American Volume 86 Number 14 (April 1902) . eing 110 volts V A. You must begoverned by the heating of your coil. Fse onlyso much current as will not heat the coil sothat the insulation burns. That would destroythe coil. A. In making a permanent magnetof tool steel, shall I first soften the steel beforemagnetizing it. or should it be hardened at theends. A. Harden the bar at the ends glasshard. (8580) H. N. B. asks: 1. Can the simple induction coil described iu lOx peri-mental Science be used to transmit messagesby wireless telegraphy V If so, how far wouldit be possible to transmi Stock Photo
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. Scientific American Volume 86 Number 14 (April 1902) . eing 110 volts V A. You must begoverned by the heating of your coil. Fse onlyso much current as will not heat the coil sothat the insulation burns. That would destroythe coil. A. In making a permanent magnetof tool steel, shall I first soften the steel beforemagnetizing it. or should it be hardened at theends. A. Harden the bar at the ends glasshard. (8580) H. N. B. asks: 1. Can the simple induction coil described iu lOx peri-mental Science be used to transmit messagesby wireless telegraphy V If so, how far wouldit be possible to transmit messages by same.A. Yes : perhaps a mile. 2. Is it necessaryto have the air exhausted from a coherer, forshort distances i A. No. 3. What is thesmallest spark which will transmit messagesabout six hundred feet, and how high a polewould be needed? A. We do not know. Per-haps a quarter inch. A pole is not required.Plates such as Hertz employed will transmitfarther than that. If you wish to use a pole,put one up a rod or so high. American Success Series. Hon. ASBURY FRANCIS LEVERtbe youngest member of Congress, was former] • secre-tary and typewriter for his predecessorfrom South Carolina Improvement the order of the age Highest typewriting possibilitiesavailable only to users of the greatSuccess, The Smith PremierTypewriter

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