A gigantic bullet?
Mark’s best analogy to describe the object is that it resembles a massive, rusted bullet. The tapered shape of the object and its oxidized exterior made it instantly recognizable. But logic soon intervened. There had never before been a weapon in history capable of storing such massive ammunition.
It had to have another purpose that was beyond Mark’s understanding. The shadows grew longer and he wondered if he had the right tools or was even meant to solve the mystery in his garden.