Important: Safety Warning
This page presents medical treatment from an era before modern medicine. The remedies described are ineffective against the conditions named, and some of the ingredients or doses are harmful. Do not use them to treat any illness; consult a qualified medical professional.
This information has been left in for historical purposes but should not be acted upon.
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Powders, Seidlitz
The cooling and refreshing drinks prepared with these powders are excellent both as refrigerant draughts and aperient medicines. Each drink requires two powders--an alkaline, generally put up in blue paper, and an acid, contained in a white one. The alkaline powder consists of two drachms of powdered Rochelle salts, and half a drachm of bicarbonate of soda, mixed together; and the acid paper of half a drachms of tartaric acid. The quantity of water employed is generally about a third of a pint. The contents of the blue paper should first be thoroughly dissolved in the water, then the contents of the white paper added, and the mixture drunk while effervescing.
This is not a beverage in the culinary sense but a measured dose of a saline purgative, written for a period when households compounded their own medicines. It is included here for the record, and the notes below explain the units and why the preparation should be left alone.
- It is a drug dose, not a soft drinkThe description of a "cooling and refreshing drink" conceals an aperient — a laxative. The whole point of the two papers is to deliver roughly 7.8 g of Rochelle salts to the gut, where it draws water into the bowel. Nothing about it is refreshing in the modern sense.
- What a drachm comes toAn apothecaries' drachm is one-eighth of a troy ounce, about 3.9 g. So the blue paper holds about 7.8 g of Rochelle salts plus about 1.9 g of bicarbonate of soda, and the white paper about 1.9 g of tartaric acid. "Half a drachms" is a printer's slip for "half a drachm".
- Rochelle salts is potassium sodium tartrateIt is a specific pharmaceutical compound, not a cooking ingredient, and a dose of this size delivers a substantial load of both potassium and sodium at once. That is exactly the reason it is unsuitable for anyone with kidney impairment, heart failure, or taking potassium-sparing diuretics, ACE inhibitors or similar medication — the last of which did not exist when this entry was written.
- The acid and alkali do not balanceThe acid and alkali do not balance exactly -- Half a drachm of tartaric acid slightly exceeds what half a drachm of bicarbonate of soda will neutralise, so what is swallowed is not a tidy tartrate solution but a mixture whose composition depends on the compounder's accuracy. Nineteenth-century formularies vary in the acid figure, which is itself a sign that the proportions were not standardised.
- Self-treating with a purgativeRepeated saline laxative use causes fluid and electrolyte loss, and abdominal pain treated with a purgative can mask appendicitis or obstruction. The entry documents a period practice of household dosing; it is not one to revive.
- The water measureA third of an imperial pint is about 190 ml, roughly three-quarters of a cup — noted only so the original is intelligible, not as a working instruction.
- If you want the effectEffervescent saline laxatives are still sold as licensed products with tested dosages and printed contraindications. Use one of those, or ask a pharmacist.
Seidlitz powders take their name from the mineral spring at Sedlitz (Czech Sedlec) in Bohemia, whose water was famous for its high magnesium sulphate content and its purgative effect; the powders were sold as an artificial substitute for taking the waters. The formula as given here does not in fact reproduce Sedlitz water at all — it substitutes Rochelle salts, potassium sodium tartrate, named for La Rochelle where it was prepared from wine-cask tartar in the seventeenth century — and the British trade in packaged "Seidlitz powders" in blue and white papers is generally traced to London chemists of the early nineteenth century, Thomas Field Savory's name being the one usually attached to it. That a general dictionary of cookery carried the recipe at all shows how thin the line between kitchen and medicine chest still was: the same book that tells you how to bone a turkey expects you to weigh out drachms of tartaric acid, and the powders were distinguished by the blue and white papers in which they were wrapped.