I'm writing a story set in the 1840s/1850s, and I need one of the characters to use dynamite. However, dynamite wasn't invented until about 20 years later. I did some research and there were other kinds of explosives in existence then, but none of them would be capable of the destruction I want to depict. So I've got two choices, either use a tool that wasn't invented yet, or exaggerate the capabilities of another tool. Which is more acceptable?