Chapter 0229: Cheers for a Hot Shower (Second Update)

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The bathhouse needed to burn hot water, a lot of it.

In this era, humans burned wood to heat water: commoners used firewood, nobles used charcoal, and there were no records of coal use—coal was likely not a product of dragons, as it is neither a metal nor a gemstone. It seemed that no humans knew about this mineral called coal, at least not in the Duchy of Sapphire.

There were also no records of other fossil fuels like oil or natural gas.

According to Liszt's speculation, given the existence of saltpeter mines and the fact that volcanoes could erupt basalt, it didn't make sense that coal, oil, and natural gas didn't exist.

But that was also uncertain.

After all, all metal ores originated from dragons, and there were no naturally formed metal ores; therefore, the absence of naturally formed coal and oil wasn't surprising.

In short, firewood and charcoal were the primary sources of fuel.