To make it easier for the good guys to fight the bad guys,
hand-to-hand combat was superceded by the bow and arrow,
which was superceded by gunpowder.
But what if an army could attack invisibly,
in a manner with which wind and gravity would not interfere,
with a "directed energy" weapon, commonly referred to as a Death Ray.
In order to build a death ray, you should first have an appreciation
of man's quest for a directed-energy weapon.
Begin with the armament developed by Archimedes, 212 years B.C.,
in defense of the city-state of Syracuse, against the superior military might of Rome.
The ancient Greek city was bound by the sea on the east coast of the Sicilian isle,
making it necessary for the Romans to approach by ship.
A giant mirror was used to focus the powerful Mediterranean sun upon the ships of war,
setting them on fire.
They called it a Heat Ray.
The device actually consisted of an array of smaller mirrors of highly polished brass
arranged in the shape of a parabola.
The radiation of the sun was directed as if passing through a colossal magnifying glass.
Unfortunately for Imperial Rome, its ships were painted with tar.
While this prevented the leakage of a considerable amount of water through the hull,
the tar also fed the flames in which the enemy ships were consumed.
Due to the intervention of the Dark Ages,
modern man did not continue his quest for directed energy arms
until the early 20th century, when his efforts resumed enthusiastically.
An English inventor by the name of Harry Grindell Matthews,
five years after the end of World War I, invented an electric ray,
which from a distance of four miles could disrupt the operation
of any engine ignited by spark, such as your typical gasoline engine.
During a demonstration to journalists, he aimed his prototype at a motorcycle in motion,
successfully stalling the engine at the distance of a quarter mile.
Given enough electrical power, he promised the long range destruction
of enemy seaship engines... tanks on the field of battle... and airplanes in flight.
Matthews initiated a bidding war for his invention between the governments of
Britain, France, and the United States.
The rights were acquired by a mysterious American investor,
whose identity was never released to the public.
Unfortunately this investor never did anything with his rights,
and when Matthews succumbed of a heart attack at the beginning of World War II,
the secret of his Death Ray was lost to the rest of the world.
Nikola Tesla was the next inventor of an invisible death ray, which he revealed in 1934.
His goal was a superweapon that would put an end to war itself.
He called it the Peace Ray.
He was experimenting with single-electrode vacuum tubes,
when a subatomic particle was liberated from the cathode, taking flight.
The particle escaped through the wall of the tube without breaking the glass.
Because at this time Tesla was bending over his experiment,
the molecular fragment struck his body.
He felt a sharp stinging pain entering his gut, and again exiting from his spine,
because the fragment had passed completely through him.
This gave him the idea for the Peace Ray, effective at a range of 200 miles,
and whether directed at the ranks of ground-based infantry, or against the pilots of a fleet of enemy aircraft,
the effect would be the same.
Any living thing in its path would perish instantly.
Tesla's device is the direct ancestor of the charged particle beam weapons
developed during the cold war by both the United States and the Soviet Union.
Today one can build a solar death ray in one's own back yard.
Focusing properly only two square yards of the sun's energy,
by employing a fresnel lens purchased on eBay,
or using a satellite dish converted into a parabolic mirror,
solid steel could be melted in seconds.
But remember this video is for educational purposes only.
Please do not attempt this at home.