Here is an architectural plan and a photograph of a German blockhouse that was constructed in Flanders during 1917. The Historian John Laffin is very informative on this subject when he refers to it in his 1997 book, The Western Front Companion:
"Blockhouses generally measured 30 ft. along the front, with a width of 10 ft. They were sunk three feet into the ground and stood 7 feet above it. The front was up to 30 inches thick. Massively strong, a blockhouse was virtually impervious to shell-fire; even a heavy shell would merely knock a large chip off the edge."
This article appears on this site by way of a special agreement with L'Illustration.
It was Lt. Commander Norman Wilkinson (1878 - 1971) of the Royal Navy who deduced that white (reflecting blue at night) was a suitable base color for naval camouflage. Wilkinson based his reasoning on the snow-capped iceberg that made such quick work of TITANIC, remembering all the while that seagulls are white, as are pelicans and the Antarctic Petrels. When the war broke out, his findings were presented to the Admiralty and it was concluded that elements of the North Atlantic fleet should be so painted. They added the black in order that the ships appear gray on the horizon.
In the spring of 1917, the German Air Corps developed a squadron of large aircraft capable of dropping 660-pound bombs on London -and drop them they did, killing as many as 788 human beings between May of 1917 and May of 1918. The Giant Goltha Bombers conducted these raids primarily at night and utterly terrified the East End of London. Eventually, German losses escalated and the London raids were canceled in favor of Paris and various other French targets. In 1917 this image of a Goltha cockpit appeared in the French press.
As a response to the drastic increase in French and British tank production, German industry manufactured a powerful (if cumbersome) anti-tank rifle in early 1918. The weapon fired a 13mm armor-piercing bullet but it's heavy recoil made the weapon difficult to operate. The Abris Museum in Albert, France has one of these currently on display.
A black and white photograph of the seldom remembered French anti-barbed wire gun.
Another anti-barbed wire invention can be read here...
"This remarkable aeroplane gun is the invention of Lieutenant-Colonel Isaac N. Lewis of the United States Army Coast Artillery Corps. Curiously enough, the gun was designed primarily for infantry and cavalry use."
Click here to read a 1918 article about the Lewis Gun.