Many people picture the scene of the whistles blowing down the lines and thousands of men climbing over the top of the parapet and charging towards the German machine guns. And although this scene is partly true, it was the prequel to this that was meant to break the defences... Artillery.

Although the development of tanks aided greatly in breaking the deadlock of trench warfare, the fact that they were not initially deployed in great numbers meant that counter tactics were quickly developed to bring these new machine to a relatively quick halt. Artillery on the other hand was a menace to trenches on both sides and this was quickly recognised by all belligerents. This is shown by the fact the Royal Artillery numbered around 548,000 men by the end of the war in over 1,700 batteries. The tactics of artillery quickly developed as the war progressed and ever increasingly became integrated within infantry units to call in fires where needed. For example more shells were fired in the 35 minute preliminary bombardment of the Battle of Neuve Chapelle than in the entirety of the Boer War. The sheer number of shells fired by the artillery led to the Shell Crisis of 1915 as production could not keep up with the rate at which the guns were firing.

Now it soon became apparent that a preliminary bombardment was not working, as the Germans had their dugouts well underground and as soon as the guns stopped firing they returned to the trenches and began firing upon the advancing troops. This is shown with the Battle of the Somme (which was not a creeping barrage) where 1.73 million shells were fired by British artillery over 8 days to relatively little effect. Now the senior British gunners developed the creeping barrage which moved forward in front of the infantry and allowing the infantry to advance behind what is essentially a screen as the Germans could not return to their trenches. This proved such a good tactic that during the Battle of Messines the British fired 3.25 million shells in their creeping barrages highlighting the high importance that the British held artillery in. This is further shown with the French essentially adopting the doctrine that the artillery conquers and the infantry occupies.

Bit of a quick overview, but if you have any further questions then don't hesitate to ask!

On Artillery, Bruce Gudmundsson 1993 King of Battle: Artillery in WW1, Sanders Marble 2016

As a follow up, how Common were machine guns during the Great War? Would certain belligerents prioritise machine guns over other weaponry?

In an original account of the Great War, Over The Top, Arthur Guy Empey describes the process in which an attack was planned, executed, and developed. He doesn't do this in a straightforward way, as far as I recall, but throughout the narrative of his book. He was injured and left the front before the use of armored vehicles. My copy is from a 1918 print run.

Intelligence was gathered from spotters, captured enemy combatants, night raids, and reconnaissance flights to assemble a map of the opposing defensive line. The brass would choose how much "weight" to throw forward and where in an assault. This plan would be augmented by deceptions and support. Deceptions might involve something as advanced as seeding false information through spies or as simple as moving troops around at night. Support could be the use of special engineer detachments, but was mostly concerned with the artillery effects.

Artillery was used continuously on many lines, but was particularly employed just prior to an assault and during. A.G. specifically lamented the use of "rolling artillery," which was intended to be a dense curtain of shelling that would advance forward in front of men moving through No Man's Land. It was not always well coordinated.

No Man's Land was not always empty. Night raids accomplished a variety of actions in between the lines; patrols screened against enemy raids, created lanes through barbed wire, took prisoners from enemy trenches, and simply expressed area superiority. Making lanes through barbed wire and relating them back through maps was very important to closing distance quickly on assault.

During an assault, the immense number of men simultaneously attacking was the main strategic choice to overcome the enemy firepower. Marginally less heartless methods of assuring a semblance of victory included smoke and gas. Smoke obscured the assault from the enemy. Gas had four effects: it wasted the enemy's time while they had to don masks, it obscured the assault, gas masks were difficult to fight or aim in, and many soldiers were terrified of the stuff.

There was another option: the night assault. On a particularly dark night it was possible to cross a significant portion of No Man's Land en masse. In the end, these were rare because it was very easy to get lost or make too much noise on the way over. Once the assaulting force was discovered the enemy artillery would fire a variety of light-shedding shells to illuminate the field.

My answer as to what the best choice for silencing machine-gun emplacements is the concentrated artillery barrage just before an assault. This has a draw-back, though. Once the guns light up in a meaningful way it will alert the enemy to any impending assault and time to prepare means more morale, more reinforcements, and their own artillery response. Enemy shelling may immediately focus on the front line to kill or rout any troops readying for assault and may barrage No Man's Land during an assault.

The layers of strategic fake-outs could become very deep when planning an assault. It was common for commanders to attempt to exploit a perceived weakness, rather than create one.

As an anti-machine gun and anti-light fortification weapon, an American version of the French Canon d'Infanterie de 37 modèle 1916 TRP light infantry gun was adopted as the "37 mm M1916" and three were provided as an optional weapon, along with six 3-inch Stokes mortars, to infantry regiment commanders.