Lant

Lant is an Old English word for aged urine. Collected urine was put aside to ferment until used for its chemical content in many pre-industrial processes, such as cleaning floors and making gunpowder.

Because of its ammonium content lant was most commonly used for floor cleaning and laundry. According to early housekeeping guides bedpans would be collected by one of the younger male servants and put away to ferment to a mildly caustic before use.

It was also recommended to freshen the breath, to flavor ale (as in "lanted-" or "double-lanted ale") and to glaze hard pastries. In larger cottage industries, lant was used in wool-processing and as a source of saltpeter for gunpowder. In times of urgent need and in districts where these were the chief industries, the whole town was expected to contribute to its supply.

"To leint ale, to put urine into it to make it strong."

"Lant. Stale urine. It was preserved in a tank and having been mixed with lime used for dressing wheat before it was sown to keep the birds from picking up the seeds."

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Wikipedia