Ammonia Cocktail

This is a dispensing-counter formula from the era when the soda fountain and the pharmacy were the same counter, and its active ingredient is a drug rather than a flavouring. The notes below explain the vessels and terms, and why the drink cannot be assembled today.

• Aromatic spirits of ammonia is the problemIt is a pharmaceutical solution of ammonium carbonate with ammonia water, alcohol and aromatic oils — the same class of preparation as smelling salts. Swallowed rather than sniffed, ammonia solution is a caustic alkali: even dilute doses can irritate the mouth, oesophagus and stomach, and the strength of any bottle labelled this way is not a culinary quantity. No amount of syrup and soda turns it into a beverage ingredient.
• "Two dashes" is not a doseA fountain dash was whatever came out of the shaker-top bottle, on the order of an eighth to a quarter teaspoonful, and it varied from clerk to clerk. Measuring a drug by an undefined splash is no measurement at all.
• The bicarbonate is there for effervescenceHalf a teaspoonful of bicarbonate of soda added last, into charged water, gives the rush of gas that made the drink feel like a restorative. Adding it last and serving quickly is the whole theatrical point — it does nothing to neutralise the ammonia.
• "A great bracer"In fountain language a bracer was a hangover or fatigue remedy sold across the counter alongside phosphates and egg drinks. It signals a medicinal claim, not a flavour profile.
• Mineral glassA straight-sided fountain glass, probably in the region of 10 to 12 ounces; filled two-thirds, that is roughly six or seven ounces of liquid in all, the ounce of syrup included. "Plain soda" means unsweetened, unflavoured charged water drawn from the fountain.
• Orange syrupThe fountain article was generally a heavy sugar syrup flavoured with sweet orange oil, often with citric acid added, and likely sweeter and more concentrated than modern orange squash or cordial. One ounce is two tablespoons.
• If you want the drinkAn orange syrup soda finished with bicarbonate is an ordinary fountain formula in its own right, and any current soda-fountain or phosphate recipe will give you one. The ammonia belongs in the history section, not the glass.