Wireless Transmission of Photographs Part 10

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CONTINUOUS WAVE WIRELESS TELEGRAPHY. Part I.

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Notes

[1] These measurements only apply to a single line. Where a double line is employed the capacity is halved.

[2] See Appendix A.

[3] See Appendix B.

[4] In wireless telegraphy "arcing" is princ.i.p.ally caused by the continuation of the supply current in the spark-gap after the capacity has been charged to a potential sufficient to break down the insulation of the gap.

[5] See Chapter V.

[6] Nernst lamps are the best to use, as they produce abundantly the blue and violet rays which have the greatest chemical effect upon a photographic film. Carbon filament lamps are very poor in this respect.

[7] A description of the apparatus required will be found in Ganot's _Physics_.

[8] Great care must be exercised in using this solution, as it is exceedingly poisonous.

[9] Two clocks would isochronise if their hands travelled at precisely the same rate round the dials, but would not synchronise unless they both registered the same time as well.

[10] Line screens can be obtained from Messrs. Penrose, 109 Farringdon Street, London; or Messrs. Fallowfield, 146 Charing Cross Road, London.