ATDDTA(11) Sending Out An S.O.S. [318:8-13]

[Keith]

[318:8-10] "To do with the *invisible* (ed., occurs about once every  
other page) new waves especially, latent in the Maxwell Field Equations"

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Maxwell's equations are a set of four equations that can all be found  
at various places in Maxwell's 1861 paper 'On Physical Lines of  
Force.' They express (i) how electric charges produce electric fields  
(Gauss's law), (ii) the experimental absence of magnetic monopoles,  
(iii) how electric currents and changing electric fields produce  
magnetic fields (Ampère's Circuital Law), and (iv) how changing  
magnetic fields produce electric fields (Faraday's law of induction).

Apart from Maxwell's amendment to Ampère's Circuital Law, none of  
these equations are original. However, Maxwell uniquely re-derived  
them hydrodynamically and mechanically using his vortex model of  
Faraday's lines of force.

In the year 1884 Oliver Heaviside selected these four equations, and  
in conjunction with Willard Gibbs, he put them into modern vector  
notation. This gives rise to the claim by some scientists that  
Maxwell's equations are in actual fact Heaviside's equations.

This matter is further confused by the fact that the term 'Maxwell's  
Equations' is also used to describe a set of eight equations labelled  
(A) to (H) in Maxwell's 1865 paper A Dynamical Theory of the  
Electromagnetic Field. It therefore helps when referring to  
'Maxwell's Equations' to specify whether we are talking about the  
original eight equations or the modified 'Heaviside Four'.

The two sets of equations are physically equivalent to all intents  
and purposes although Gauss's Law is the only actual equation that  
appears in both sets. The Lorentz force that appears as equation (D)  
in the original eight is the solution to Faraday's law of  
electromagnetic
induction that appears in the 'Heaviside Four', and the Maxwell/ 
Ampère equation in the 'Heaviside Four' is an amalgamation of two  
equations in the original eight.
   http://en.wikipedia.org/wiki/Maxwell%27s_equations

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[318:10] "years before Hertz found them"

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Earlier in 1886, Hertz developed the Hertz antenna receiver. This is  
a set of terminals that is not electrically grounded for its  
operation. He also developed a transmitting type of dipole antenna,  
which was a center-fed driven element for transmission UHF radio  
waves. These antennas are the simplest practical antennas from a  
theoretical point of view. In 1887, Hertz experimented with radio  
waves in his laboratory. These actions followed Michelson's 1881  
experiment (precursor to the 1887 Michelson-Morley experiment) which  
did not detect the existence of aether drift, Hertz altered the  
Maxwell's equations to take this view into account for  
electromagnetism. Hertz used a Ruhmkorff coil-driven spark gap and  
one meter wire pair as a radiator. Capacity spheres were present at  
the ends for circuit resonance adjustments. His receiver, a precursor  
to the dipole antenna, was a simple half-wave dipole antenna for  
shortwaves.
   http://en.wikipedia.org/wiki/Heinrich_Rudolf_Hertz

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[318:10-13] "---Shunkichi Kimura, who had studied with Gibbs here,  
had returned to Japan, joined the Naval Staff college faculty, and co- 
developed wireless telegraphy in time for the war with Russia.  
Vectors and wireless telegraphy, a silent connection."

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At the end of the 19th Century, when tensions were mounting between  
Russia and Japan, Marconi asked such a high price for his  
radiotelegraphic equipment that the Japanese navy invited Sendai's  
http://en.wikipedia.org/wiki/Sendai "Second High School" teacher,  
Shunkichi Kimura, who was developing his own wireless technology and  
teaching it to his students, to become an officer in the Navy. Prof.  
Kimura developed the "Meiji 36 type radiotelegraph," and Japanese  
vessels were built to be equipped with it.

When war broke out in February, 1904, the Japanese were clueless  
about from whence the Russian fleet would mount its attack. The  
Japanese cruiser SHINANO MARU, while patrolling the East China Sea  
near the mouth of the Tsushima Straits, spotted the Baltic Fleet on  
May 27, 1905, and telegraphed their location to the Japanese fleet,  
giving them strategic advantage, allowing them to annihilate the  
Russians in the Sea Battle of the Tsushima Straits, one of the most  
devastating victories in the history of naval warfare.

from:
_History of Wireless_
Authors: Tapan K. Sarkar, Robert J. Mailloux, Arthur A. Oliner,  
Magdalena Salazar-Palma, Dipak L. Sengupta
Chapter 14: The Antenna Development in Japan: Past and Present (p  
455-472)
   http://www3.interscience.wiley.com/cgi-bin/bookhome/112100918/

--

The Battle of Tsushima, commonly known as the “Sea of Japan Naval  
Battle” in Japan and the “Battle of Tsushima Strait” elsewhere, was  
the last and most decisive sea battle of the Russo-Japanese War of  
1904–1905. It was fought on May 27-28, 1905 (May 14-15 in the Julian  
calendar then in use in Russia) in the Tsushima Strait. In this  
battle the Japanese fleet under Admiral Heihachiro Togo destroyed two- 
thirds of the Russian fleet under Admiral Zinovy Rozhestvensky. In  
_Theodore Rex_, historian Edmund Morris calls it the greatest battle  
since Trafalgar. It was the biggest naval battle of the pre- 
dreadnought battleship era.

The Battle of Tsushima was the only sea battle in history in which  
steel, engined-powered battleships fought a decisive fleet action. In  
addition, much to the Russian Navy's credit, Admiral Rozhestvensky's  
battleship fleet conducted a voyage of over 18,000 nautical miles (33  
000 km) to reach their Far Eastern station.

Prior to the Russo-Japanese War, countries constructed their  
battleships with mixed batteries of mainly 150 mm (6-inch), 203 mm (8- 
inch), 254 mm (10-inch) and 305 mm (12-inch) guns, with the intent  
that these battleships fight on the battle line in a close-quarter,  
decisive fleet action. The battle demonstrated that the big guns with  
longer ranges were more advantageous and favourable during naval  
battles, not mixed batteries of different sizes. As early as 1904,  
the Imperial Japanese Navy developed the Satsuma (laid down a few  
days before the Battle of Tsushima, on May 15th, 1905), the first  
ship to be developed and laid down as an all-big-gun battleship.  
Great Britain would soon follow suit, laying down the keel of HMS  
Dreadnought in October 1905, and becoming the first to complete an  
"all big gunned" battleship (305 mm cannons). HMS Dreadnought was  
launched in 1906, and created the separating date between "Pre- 
Dreadnoughts" prior to 1906 and "Dreadnoughts" from 1906 afterward.  
http://en.wikipedia.org/wiki/Battle_of_Tsushima

--

Josiah Willard Gibbs (February 11, 1839 – April 28, 1903) was a  
preeminent American mathematical-engineer, theoretical physicist, and  
chemist noted for his famed 1876 publication of On the Equilibrium of  
Heterogeneous Substances, a graphical analysis of multi-phase  
chemical systems, which laid the basis for a large part of modern-day  
science. Being one of the greatest American scientists of the  
nineteenth century, he devised much of the theoretical foundation for  
chemical thermodynamics as well as physical chemistry. As a  
mathematician, he was an inventor of vector analysis. He spent his  
entire career at Yale, which awarded him the first American Ph.D. in  
engineering in 1863.
   http://en.wikipedia.org/wiki/Willard_Gibbs

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