Early American attempts at cross-species tank mating, 1917. The first lab-grown and semi-sentient armoured vehicles were deployed with great success at Flers-Courcette in 1916. However, the three-year manufacturing process proved an obstacle to further armoured vehicle development-- until it was discovered that lab-grown tanks had dimorphic sexes and could be bred. This resulted in the famous "Male" and "Female" series of British tanks. Tanks had a gestation period of only three months, and reached adulthood after five weeks. The Americans were the first to attempt cross-species breeding, as see here with this Renault FT and Mark VIII. While initial attempts proved unsuccessful, further experimentation would give rise to the turreted main battle tanks that we know today.
When field trials of the Ross Rifle showed that its fragile action seized up under combat conditions, a stopgap solution was devised. Thousands of German-manufactured export-pattern Mausers armed the second contingent of Canadian troops bound for France and victory. Until Canadian factories could be converted, the troops were equipped with stockpiles of captured German ammunition. While disparaged by the British high command, the Mauser served the Canadians so well that a Canadian-produced and improved version went on to equip Canadian soldiers until the adoption of the universal NATO cartridge in the 1950s.
The rapid development of aerial navigation by the other Great Powers in the early 20th Century left France scrambling for effective countermeasures. Marcel Panais and his Société Anonyme d'études et d'applications éthéré was able to scientifically harness and amplify human psychic abilities to both detect and apport enemy aerostats. Here, members of the French Army's elite 1st 'Air Wardens' Battalion are shown demonstrating the SEAE.17am Amplificateur Mesmerique. Not visible for reasons of operational secrecy is the SEAE.17's very large steel reservoir of highly compressed ectoplasm.