Various Tesla book cover images

Nikola Tesla Books

Books written by or about Nikola Tesla

Nikola Tesla: Colorado Springs Notes, 1899-1900 Page 397

June 1

Tesla mentioned a similar application of a magnet for extinction of the arc in rarefied gas in his lecture to the IEE in London 1892(5). The initial idea for this type of detector may date from the time he was intensively studying phenomena associated with currents in vacuum.

June 3

During the year 1899 Tesla filed applications for four patents{8, 9, 10, 11) which made use of the principle of “accumulating energy of feeble impulses”. It may be seen from these patents that the function of the capacitor was to store energy from the commutated (in fact rectified) HF current. The condenser is connected to the receiver (a relay) which periodically makes contact(8, 10) when the condenser charges up enough. Both these patents were filed 24th June 1899(9, 10). The other two(9, 11) were filed 1st August 1899. They also refer to a method of accumulating energy but the way the incoming signal controls the charging of the condenser is different: here it causes variations in the resistance of a “sensitive device” which controls the current charging the condenser from a battery. The condenser discharges periodically through the receiver as in the previous case.

Tesla developed the magnet method while he was in Colorado Springs.

June 5

Tesla does not state the origin of the formula he uses to calculate M, the power induced in the secondary, receiving coil, by the primary fed with a power of 4 kW (or 4 x 1010 erg/sec, not ergs). Although he himself expresses doubts about the calculation, the conclusion he draws is correct, i.e. that these mode of transmission is greatly inferior to that which he calls the method of “disturbed charge of ground and air”, in fact that of electromagnetic radiation.

June 6

Working with a darkened Crooke's tube, on the 8th of November 1895 RÓ§ntgen noted the luminescence of barium platino-cyanide crystals and discovered that it was due to some unknown radiation which he termed X-rays. Towards the end of that year he held a lecture on his discovery, and in an amazingly short time the whole world knew about his work(66).

397

66

Bowers B. X-RAYS, Science Museum, London, 1970.

Contents

Introduction
June 1 - 30
July 1 - 31
August 1 - 31
September 1 - 30
October 1 - 31
November 1 - 30
December 1 - 31
January 1 - 7
Commentaries

Appendices: I, II

Images

Glossary

Lowercase tau - an irrational constant defined as the ratio of the circumference of a circle to its radius, equal to the radian measure of a full turn; approximately 6.283185307 (equal to 2π, or twice the value of π).
A natural rubber material obtained from Palaquium trees, native to South-east Asia. Gutta-percha made possible practical submarine telegraph cables because it was both waterproof and resistant to seawater as well as being thermoplastic. Gutta-percha's use as an electrical insulator was first suggested by Michael Faraday.
The Habirshaw Electric Cable Company, founded in 1886 by William M. Habirshaw in New York City, New York.
The Brown & Sharpe (B & S) Gauge, also known as the American Wire Gauge (AWG), is the American standard for making/ordering metal sheet and wire sizes.
A traditional general-purpose dry cell battery. Invented by the French engineer Georges Leclanché in 1866.
Refers to Manitou Springs, a small town just six miles west of Colorado Springs, and during Tesla's time there, producer of world-renown bottled water from its natural springs.
A French mineral water bottler.
Lowercase delta letter - used to denote: A change in the value of a variable in calculus. A functional derivative in functional calculus. An auxiliary function in calculus, used to rigorously define the limit or continuity of a given function.
America's oldest existing independent manufacturer of wire and cable, founded in 1878.
Lowercase lambda letter which, in physics and engineering, normally represents wavelength.
The lowercase omega letter, which represents angular velocity in physics.