What Was The Gas Price In The 1700's?

Engines using gas as a fuel were not yet present in the 1700s.  The mixture known as petrol or what we might even begin to refer to as gasoline was only sold is small bottles as a treatment to cure head lice infections, and so there was no per gallon/liter price established,  Gasoline was not sold in bulk to consumers, and whatever price for these small bottles was highly variable, depending on where it was sold and independently made.  There was no mass manufacture of it, obviously.

Yea come on now, cars begin in the early 20th century... Maybe if you farted in public and someone thought it was amusing you have received a penny for your embarrassment...