Various Tesla book cover images

Nikola Tesla Books

Books written by or about Nikola Tesla

body of experimenter connected to free end, the spark between the same points. As it was sure that the vibration of coil was too slow for the impressed vibration of approximately 50,000, wire was gradually taken off.

Number of turns on coil Longest spark from free end to body of experimenter Longest spark from watermain end to body of experimenter Longest spark between the two ends of coil without capacity Longest spark between the two ends of coil with capacity of experimenter on free end

 

Observation
I. II. III. IV. V. VI.
448 1/8" 5/64" scarcely visible scarcely visible  
420 1/8"+d 5/64" " "  
392 1/8"+d 5/64" " "  
364 3/16" 3/16" " "  
336 3/16"+d 3/16" small spark small brighter spark  
308 1/8" 3/16" " spark larger  
294 5/32" 5/32" " livelier spark  
280 1/8" 1/8" " "  
266 3/32" 3/32" " "  

Indications up to present confirm detrimental effect of capacity. A coil was now added in series. This coil was one used often in New York and was wound on a drum 30" diam. There were about 150 turns total length of wire 1125 feet. To this added the 266 turns of experimental coil giving length of 6.5 feet per turn made length 2100 feet for exp. coil or total 3225 feet. This was very near quarter wave length as it ought to be. Now results were

I. II. III. IV. V. Observ.
266+150 7/16" 3/32" 3/32" 3/32" lively  
Exp, additional coil          

Experiments were now continued with experimental coil alone and showed

252 1/8" 1/8" less d small spark small spark livelier Observ. The distributed capacity unmistakably prevents rise on end.
224 3/32" bright 1/16"  ”
196 1/16" 1/16" less d
168 1/16" 1/16" ” practically the same.

175

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.