Firstly,by early 1915 both sides had constructed continuous trench lines stretching from the North Sea coast of Belgium to the Swiss border. This made it impossible for either side to outflank the other,so all attacks had to be head on frontal assaults,easy for the enemy to see coming,so surprise attacks also became impossible.

Secondly,modern weapons were able to deliver massive firepower over a large area in a short space of time. Belt fed machine guns,rapid firing breech loading artillery,and magazine loaded bolt action rifles, used by defenders sheltering in entrenchments, gave defenders a big advantage over attackers in battle.

Armies were much bigger in WW1 than ever before.The Prussian army that invaded France during the Franco-Prussian War of 1870-1871 was less than 300,000 men.The German army involved in the Schlieffen Plan in 1914 was 4 million strong.Other European armies grew to comparable size during WW1, so the entire trench line could be manned fully,and their were always plenty of reserves available if an enemy attack looked like it might break through.There were therefore no weak spots in the enemy front to attack.

Finally, the senior commanders on both sides were elderly,unimaginative,and narrowminded.They couldn't think up any other form of attack than a mass frontal assault preceded by a heavy artillery barrage (just to be sure the enemy knew they were coming).

A combination of the above factors meant that a stalemate developed on the Western Front from the beginning of 1915,as it was too difficult to break through the enemy trench lines.

The first discourse on the topic of the speed of light appears to originate from the ancient Greek society of philosophers. Aristotle, a highly regarded philosopher at the time contradicted a fellow philosopher Empedocles on the speed of light. Empedocles argued that because light moved; some time to travel must be present. Aristotle however was under the impression light was to travel instantaneously. This later led to further discussion and further experiments being undertaken.
(Scienceblogs.com/startwithabang/2011/09/12). The current value accepted world wide as the speed of light is 299,792 km/s (Speed-light,info/measure-speed-of-light.html). In this report I will be highlighting four key scientists; Ole Roemer, Galileo, Leon Foucault and Fizeau who I believe contributed most significantly to what was once just a scientific concept.
Scientist Year Approach Value of C estimation
Galileo 1638 Lanterns 10 x faster than sound
Roemer 1675 Jupiter 200,000 km/s
Fizeau 1849 Mirror reflection 313,300 km/s
Foucault 1862 Mirror reflection 299,796 km/s Galileo
“Everyday experience shows that the propagation of light is instantaneous; for when we see a piece of artillery fired at great distance, the flash reaches our eyes without lapse of time; but the sound reaches the ear only after a noticeable interval” (http://galileoandeinstein.physics.virginia.edu/lectures/spedlite.html_)
Galileo in this quote clearly points out nothing can be deduced from this observation other than light travels faster than sound. The idea Galileo had synthesised was that two people would be a known distance e.g.: 1 km apart from each other; both equipped with covered lanterns. One would un-cover their lantern followed by the person 1km away once they saw the light from the other lantern.
This experiment was first practiced at close distances, so Galileo and his assistant were able to become accustomed to the reaction times involved. They were then to attempt it from 1 – 3 miles apart, potentially further using telescopes in order to see if the interval time is perceptibly lengthened. (Speed-light,info/measure-speed-of-light.html) Galileo Claims to have done the experiment at a distance under one mile and could not detect any time lag. Galileo was right in saying that light travelled faster than sound however his estimate of ten times faster was a cut below;