Hi Charles
Thanks for sharing that story! Just goes to show how easy we have it now.
Often times recipes were passed down from mother to daughter and so on.
In the movie "The Little Foxes" Adie is putting Alexandrea on the train to fetch her father... Adie instructs her how to behave on the trip, witch includes not using any other soap except the one she had made for her!
Some old time recepies were time honnored secrets, hardly ever shared!
Even now, Soap Makers don't reveal all their secrets, especially if they have come up with a luxury formula. Ingredients are listed, but not the percentages of ingredients. Those percentages oddly enough make a world of difference in the final products performance, feel, look, smell, lather ect.
Laundress
thanks for looking, the one I use is 16 ounces, and I believe some of the old vintage metal cans held 10 ounces . So one can of lye could have easily made 5 to 6 lbs of soap, depending on the fat.
Now a days soap formulas are created with a SAP chart, and a digital scale.
The weight of the soap that is going to be made, or the batch size is decided first.
The SAP chart shows the amount of sodium hydroxide required to saponify all of a specific fat, or oil. (By weight)
Each fat that is going to be used, has to be calculated seperateley, as each fat has a different SAP value. And, I've always found this interesting, but no two fats, be they animal or vegetable are exactly alike in their fatty acid makeup
Hence my curiosity of the vintage label.