The Mark IV Churchill tank had a 40 mm cannon. Various configurations were tested before they went into serial production. Initially, it was planned to arm the Churchill with a three-inch caliber howitzer, but thanks to General Vyvyan Pope's opposition to the project, among others, the project was abandoned. 1)
At the outbreak of the Winter War with the USSR in 1939, the Finnish army had about 60 tanks, including 32 obsolete Renault FTs and 26 Vickers tanks. During the war, the Finns captured plenty of Soviet tanks, mostly T-26s. 2)
Brown powder, which burns slower than black powder, allowed the use of longer barrels, improving the accuracy of firing. With less stress on the guns, they became more durable and their construction more accurate. 3)
The 23rd Headquarters Special Troops, also known as the Ghost Army, was responsible for fooling the Germans into believing that the D-Day landings would take place in Pas-de-Calais rather than Normandy. Each time, wherever they were ordered to camp, a thousand ghosts pretended to be a 30,000-strong army. This was made possible, among other things, by playing over huge loudspeakers the sounds of loud tank engines growling, infantry marching, commands, etc. 4)
Sultan Mahmud II of the Ottoman dynasty, who ruled from 1808 to 1839, abolished the Janissaries in 1826, a move that greatly facilitated subsequent political reforms. The Janissary community, conservative and opposed to any changes, was at times a threat to the sultans, especially those following the ideas of modernization of Turkey. Osman II, on the other hand, was liquidated by the Janissaries. 5)