saleratus

Buttermilk or sour milk with a tea spoonful of saleratus, is better to mix with the Indian meal, than sweet milk and eggs.

From The New England Cook Book, or Young Housekeeper's Guide Being a Collection of the Most Valuable Receipts; Embracing all the Various Branches of Cookery, and Written in a Minute and Methodical Manner by Anonymous

You can tell why—his face with all those yellow freckles looks like an old fashioned saleratus biscuit.

From The Corner House Girls on a Tour Where they went, what they saw, and what they found by Grace Brooks Hill

Some housekeepers soak ripe peas over night, in water in which they have dissolved a little saleratus.

From Vegetable Diet: As Sanctioned by Medical Men, and by Experience in All Ages Including a System of Vegetable Cookery by William A. (William Andrus) Alcott

Some use bolted meal; most raise bread by fermentation; many use salt; some saleratus, or carbonate of potash; and, in the country, many use milk instead of water to form the paste.

From Vegetable Diet: As Sanctioned by Medical Men, and by Experience in All Ages Including a System of Vegetable Cookery by William A. (William Andrus) Alcott

If your yeast appears to be sour, put a little saleratus in just before you put it into your bread; if it does not foam well, it is too stale to use.

From The New England Cook Book, or Young Housekeeper's Guide Being a Collection of the Most Valuable Receipts; Embracing all the Various Branches of Cookery, and Written in a Minute and Methodical Manner by Anonymous