Like what I make? Want fewer sponsorship ad reads? Consider contributing to my Patreon at https://patreon.com/OurOwnDevices While today we don't tend to think of balloons as weapons of war, they in fact have a long and proud military heritage stretching back to the 1790s. The heyday of the military observation balloon was the First World War, when detectors like this one would have been issued to find leaks in the balloon envelopes.