Soap Day the Old Way: Lye from Ashes

The Pocumtuc Housewife, published in Deerfield, Massachusetts, in 1897 “by several ladies,” was written for young wives new to the Connecticut Valley. Along with its recipes, it gives “plain directions for soap-making” as the old valley households did it ¹.

The soap-grease barrel

Soap day started a year ahead. Keep a soap-grease barrel in the cellar with some weak lye in it, and drop in bacon rinds, bits of fat meat, the fat skimmed from boiled salt meat, darkened cake fat, “and everything fat that comes along.” The lye works on it and keeps it from spoiling. “It is amazing how much comes along in the course of a year” ¹.

The ash leach

In spring, when the ash hole was cleaned out, five or six bushels of wood ashes went into the ash leach. Without one, a hogshead, a big barrel, with holes bored in the bottom and set up on sticks would do ¹:

1. Pour on enough water to wet the ashes thoroughly, but not so much that they drip, and let them stand several days.
2. Then pour on boiling water and let it drip into a tub. Keep adding water until the lye coming out grows weak.
3. Test the strength: if the lye is strong enough to hold up an egg so that a patch about the size of a ninepence coin shows above the surface, “it is about right.”

Soap day

On soap day, get breakfast out of the way early and plan an easy dinner. Swing the big six-pail kettle on the crane over the fire, and heat the grease with some strong lye in a smaller kettle. As the grease dissolves, ladle it into the big pot, adding more lye and water. “A little experience will teach how much of each.” Too much lye makes the soap thin, and it “will eat your clothes and your hands.” Water makes it jell, but too much and it won’t keep. Boil until it becomes thick and ropy ¹.

If it doesn’t “come,” take out a little in a dish and try adding water, then lye, then grease, until the sample thickens; then add whatever it needed to the big pot and boil again ¹. That was the old way to troubleshoot without a scale.

What came out of that kettle was a jellied soap, softer than the hard bars of the last lesson. The 1942 Michigan bulletin’s rescue method, boiling with water until it looks like honey, is essentially the same process ².

Why we use store lye now

Ash lye is still caustic, and it burns skin and eyes just like store-bought lye ³. Its strength varies with the ashes and the water, which is why the old directions measured by eggs and experience instead of ounces ¹. Weighed lye and the 1942 recipe’s measured fat make predictable soap. Make ash lye once to understand the old way, with goggles and gloves, and use it for a small kettle batch rather than hard bars.

Try it

Fill a bucket with holes drilled in the bottom with hardwood ashes from a wood stove, set it on bricks over a glass or enamel pan, and pour hot water through it. Try the old egg test on what drips out. Handle the liquid with gloves and goggles, as you would any lye.