Back in the old days palatable fat was a scarce resource, and was not wasted.
It was eaten.
Tallow was not only used as a lubricant but eaten too, so another ‘do not waste’ resource
Tar oil was produced in large quantities, mainly in the Finnish part of Swedish realm. Exported.
Made by the farmers and forestry workers in thousands of small kilns.
To dilute the unpalatable, rank fat that could not be eaten and some of the excess tallow they used the tar oil.
I suspect they used what we call Ryssolja ( Russian Oil) made from Birch bark. This was used to treat leather.
This was the soap they made in the farms. Home made soap that they used at least a couple of times a year.
Because that is how often they had a full body wash!
When they discovered it was efficient against some skin conditions it became medicinal too, no doubt with more tar added (?)
In the past, most people suffered from skin problems. Small localized infections, infected bug bites.
Oldfashioned Carbolic soap is very nasty on the skin. Own experience from youth.
