Richard Jordan Gatling, a somewhat famous inventer, claims he has come up with an idea for a revolutionary new weapon to give the Union a technological edge with. His previous inventions include a screw propeller and a wheat drill in 1839, and a hemp break machine in 1850. All of these have helped progress the agricultural industry of the US.
The Union funds him and places him under protection, but even with funding he says he will need a few years to make the design practical.
A similar story appears with the inventor Walter Hunt, who is notable for inventing the lockstitch sewing machine in 1833. He claims to have found yet another revolutionary design for a weapon, and he's coined this new type of rifle as a repeater. That being said, he still has much work to do.
He's placed under protection and is funded, similar to Gatling.
