At the beginning of the war Germany was using the prewar 7.7cm Feldkanone 96 n.A. field guns on improvised mounts for anti-aircraft work.

In September 1915, German anti-aircraft crews accounted for approximately twenty-five percent of all allied aircraft shot down on the Western Front.

By the fall of 1917, the German army began introducing more motorized flak units (Kraftwagenflak or K-flak) consisting of a 7.7mm gun mounted on the bed of an open truck.
The mobility of these guns allowed for more rapid deployment along the frontlines.
In fact, the primary mission of these guns involved the combating of low-flying allied aircraft near the front.

German motorized flak guns increased from thirty-eight in February 1916 to fifty-six by May 1916. By the end of the war, the Germans had 800 motorized flak guns. Most were manufactured by two factories, Krupp of Essen and Rheinmetall-Borsig.

The Gun Carrier Mark I, the first piece of self-propelled artillery ever to be produced and were first used in the Battle of Pilckem Ridge during the Third Battle of Ypres.

During 1916 it became clear that in case of a breakthrough, the very purpose of the first tank, the Mark I, artillery would have great trouble following the advancing troops. Any successful offensive would therefore be in danger of stalling immediately. To solve this problem, Major John Greg, an engineer working for the main tank producing company Metropolitan, Carriage, Wagon and Finance, proposed to build special mechanised artillery, using parts of the Mark I. 

As you can see the vehicle bore little resemblance to the Mark I however it retained the Daimler 105 hp engine and transmission of the Mark I. 

This structure also housed the vehicle commander, a mechanic and two gearsmen. The original double tail wheel of the Mark I (intended to aid steering but often omitted in action) was attached to the rear of the vehicle and seems to be retained in photographs.

The front section the tall narrow structures at each side, that acted as armoured cabs for driver on the left and brakesman to the right. Between these two structures lay a low-slung pivoting platform able to accommodate a 60-pounder (5-inch) gun, a 6-inch 26 cwt howitzer or any equivalent in stores or personnel.

This platform acted as a loading ramp, down which a loading trolley or cradle could be lowered and positioned beneath the gun carriage. The wheels of the gun were removed and attached to the side of the carrier until needed again. The carriage was lowered onto the trolley which could then be winched up onto the platform using a pair of engine-driven winding drums. Spaces to the rear of the cabs were used to store up to a hundred rounds of ammunition for the howitzer in addition to other warlike stores.

The production of a prototype was approved on 5 June 1916; the actual design began in July. The first prototype was ready to participate in the Tank Trials Day at Oldbury on 3 March 1917. An order of fifty vehicles was given to Kitson & Co. in Leeds. Deliveries to the army started in June and ended in July of the same year. 

Two vehicles out of the order of fifty were finished as Gun Carrier Cranes, salvage tanks with a hand-operated crane in the front but without the distinctive pair of forward cabs.

In July 1917, two Gun Carrier Companies were formed of 24 vehicles each. Probably none of them ever fired a shot. As breakthroughs never materialised the vehicles were ultimately only used as supply tanks.

The Renault FT 75 BS self propelled gun.

This modified Renault FT was one of the early self propelled guns. Designated the 75 BS it was fitted with a short barreled Blockhaus Schneider 75mm gun, around 39 were thought to have been produced.

Glimpses of The Great War, the Granatenwerfer 16

Developed in the Austro-Hungarian army, the Granatenwerfer 16 was a German WWI grenade thrower which bridged the gap between hand-thrown grenades and the light minenwerfers. Throwing a small grenade with a 400g (14oz) high explosive charge to a maximum range of about 300 meters (330 yards) , the Gr.W.16 with a practiced crew could maintain a rate of fire of 4-5 rounds per minute.

It was a classic example of the spigot mortar type weapon. Rather than having a hollow barrel into which the projectile fit, it had a simple rod with a firing pin built in. The grenade it fired had a hollow center shaft, which fit onto the firing rod. To fire, a gunner (a 2-man crew, in practice) would first adjust the spigot rod to the correct angle for the desired range, depress the cocking collar until the firing pin was cocked, rotate the safety lever to the “safe” position, insert a fuse into a grenade (they were fairly sensitive impact fuses), slide the grenade onto the launcher, remove the safety pin, and fire the grenade by means of a lanyard pull.

Glimpses of The Great War, the Imperial Camel Brigade.

The Imperial Camel Brigade was formed on 19 December 1916 for service in the Middle East. The brigade originally comprised three battalions, 1st (Australian), 2nd (British), and 3rd (Australian), plus supporting units. Each of the battalions had an authorised strength of 770 men and 922 camels. A battalion comprised four companies and a headquarters. The 4th (ANZAC) Battalion was raised in May 1917, but instead of increasing the brigade fighting strength, it was decided one battalion would always be resting and refitting, while three battalions served at the front.

The lines of the Imperial Camel Corps shaded by trees near Beersheba.

Men of an Australian and New Zealand Army Corps battalion of the Imperial Camel Corps Brigade

To complete the brigade structure and supply added firepower, the brigade received some other units: the 265th (Camel) Machine Gun Squadron, with eight Vickers machine guns, and the Hong Kong and Singapore (Mountain) Battery, armed with six BL 2.75 inch Mountain Guns. 

The Hong Kong-Singapore Mountain Battery of the Imperial Camel Corps, the camels are carrying Vickers 2.75 inch (70 mm) MK 1 Mountain Guns and other supplies.

Artillery support for the Imperial Camel Corps Brigade was provided by the Hong Kong and Singapore (Mountain) Battery, Royal Garrison Artillery. 1918

Despite their title, the battery was formed by men from the British Indian Army. The brigade included the ICC Mobile Veterinary Section, and the brigade's logistic units were the ICC Brigade Ammunition Column and the ICC Brigade Train, which carried enough supplies for five days. The total brigade strength was around 4,150 men and 4,800 camels.

Glimpses of The Great War, the early 8-inch howitzer.

Changing a barrel, which occurred frequently. Battle of Polygon Wood, September 26, 1917

The BL 8-inch howitzer Mark I through to Mark V (1 to 5) were a British improvisation developed early in the war to provide heavy artillery. It used shortened and bored-out barrels from various redundant naval 6-inch guns.
It bore no relation to the later 8-inch howitzer of the First World War, the Vickers 8-inch Mark VI to VIII howitzers which succeeded it.
The weapon entered service in February 1915.
The Mark I–V had many relatively minor differences in the carriages and trails and Mk IV, Mk VI and QF Mk II 6-inch naval gun barrels were used. However, the ballistic characteristics, propellant charges and shells used were similar for all Mks I–V. They are easily identified by their short thick barrel and twin recoil buffers above the barrel.
Mks I–IV were no longer repaired from summer 1917 onwards.

8 inches (204 mm) heavy guns in battery on the Somme in 1916

At almost full recoil after firing

8 inch howitzer in action September 1916 LAC 3194238

8 inch howitzer 

Glimpses of The Great War, "The Monsters"

The first encounter with a war tank, the account of an anonymous German soldier.

" my blood froze in my veins. Crawling along the battlefield punished by artillery were two mysterious monsters. The Monsters approached slowly - trepidando, staggering, swinging - but no obstacle could stop them, they always advanced with a supernatural force. Our machine guns and hand grenades simply didn't affect them. They were able to easily crush our crews in craters, then cross the German front line and exit to the village of Flers, where they stayed for some time. The British Infantry that followed them took possession of the village, and the machines overthrew the road-Tilloy road."  (A Primeira Guerra Mundial)

The British produced the world's first tank, tracked and armed armoured vehicle, to enter combat. Beginning with the Mark I which entered service in August 1916. It was first used in action on the morning of 15 September 1916 during the Battle of Flers-Courcelette, part of the Somme Offensive. With the exception of the few interim Mark II and Mark III tanks, it was followed by the largely similar Mark IV, which first saw combat in June 1917. The Mark IV was used en masse, about 460 tanks, at the Battle of Cambrai in November 1917. The Mark V, with a much improved transmission, entered service in mid-1918. More than two thousand British heavy tanks were produced. Manufacture was discontinued at the end of the war.

Mk IV drawing