system
Given the following post, respond as if you're commenting on Reddit:
human
What does "cooking" dynamite into "grease" mean?

Big fan of Prohibition-era non-fiction and in a memoir I read of a safecracker, he talks of the explosives -- aka "grease" -- he would use to open safes:

*"Shooting a box is real touchy because the grease that you're using is cooked out of dynamite and it's not the same consistency as nitroglycerin that you buy. Sometime it may be real strong and next time weak and there's no way to tell until you try it out."*

He doesn't mention anything else about it and I've Googled this from every angle I know how. What does he mean by "cooked"? Literally, in an oven or on the stove? What is all even in that "grease"? Is it soupy or solidified?

EDIT: I'm now aware of Nobel having made nitroglycerin safer by inventing dynamite so that's cool.
gpt
"shooting" is blasting slang for detonating. "A box" is referring to either the safe or the case of dynamite. "Grease" is a reference to nitroglycerin mixed with any number of additives that were used in manufacturing dynamite . Nitroglycerin can be made from saturated fats, so "grease" is an apt slang term. Texture wise, it's a viscous, oily liquid. Think about the consistency of liquid hand soap or a little thicker.  "Cooked out" refers to the impure nitroglycerin that has settled or sweated out of the dynamite. Old processes of manufacturing dynamite allowed the nitroglycerin to settle out and weep through the casing of dynamite. Since the nitroglycerin from dynamite contains additives, it isn't the same viscosity as pure nitroglycerin. The additives also affect the properties of nitroglycerin, potentially changing detonation rate, so you wouldn't know how powerful the detonation would be unless you had "shot" this particular brand before. The amount that had weeped out could also change detonation rate since it's no longer impeded by the filler it was soaked into.