The “frog mug” is perhaps an unlikely subject for Wikipedia, but so great is that resource I have learned not to minimize it. Indeed a well-written history appears just on that subject, authored apparently by a botany expert.
The mug took different forms, as a cursory image search shows, but the classic type has the little animal crouched at the base, looking up to startle the drinker when the drink descends far enough to see him. In the old days alcoholic drinks were often cloudy – ale, cider, perry and the like – so the drinker did not suspect a jape until thrust upon him or her. The world turns – cloudy drinks are in vogue again – so perhaps the frog mug is due for a revival.
The essay noted explains the mug as a simple joke, originating in the mid-1700s in districts where pottery was produced. Clearly a macabre humour is at work here, but there has to be more to it than that to explain the origins of the practice, one that quickly spread to the New World, as numerous accounts refer to the mug from American Colonial days and into the present.
Going deeper, one explanation, offered in Cheshire Notes and Queries of 1883, states the practice derives from a northern superstition. A frog was sealed in a pot of some kind, over which an invocation was chanted to place ill wishes on an enemy. The idea was the animal would expire slowly and hence too the object of the curse would take sick and wither in parallel. The writer projects that makers of mugs then had the idea to place a frog in the mug for a sly visual joke, and states servants quarters in gentlemen’s houses often featured the item.
Yet Jane Perkins Claney, in her 2004 book-length study of Rockingham Ware in American culture, states the frog, less the toad though, was a fertility symbol in some cultures and the frog mug may be a beneficent practice to recall this early belief.
In this 1878 issue of the The Cultivator and Country Gentleman, it is explained (without reference to frog mugs as such) that a mother of vinegar was added to some cider to hasten its conversion to vinegar. A mother of vinegar is a mass of cellulose and Acetobacter, a bacterium that produces acetic acid under the influence of oxygen. The account likens the mother to the scum on a stagnant pond, known popularly, it states, as “frog spittle”.
Other accounts confirm the popular term frog spittle to describe growth on a pond, which is vegetative in origin, nothing to do with frog emanations as such.
So perhaps (Beeretseq thinking here) cloudy, yeasty beer or cider reminded drinkers of this pond matter, and from there, someone had the idea to place a “swimming” frog in the base of the pot to complete the analogy. Indeed a 1970s joke among those not enamoured of “real ale”, the unfiltered, still-fermenting beer form fancied by connoisseurs, was the “pond matter” often drifting in the beer.
Yet another explanation occurs to us: a toadstool is a mushroom, which is a fungus. Yeast, which ferments apple juice into cider and a boiled cereal mash into beer, is also a fungal organism. The idea of toadstool/mushroom transferred to placing a facsimile of a toad or frog in the beer pot, to make a punning style of joke.
These various explanations may have merged over time with the true origins being forever lost.
On Twitter recently the U.K. beer writers Boak and Bailey mused about fashionable pub names that seem derived from a non-pet animal and an item of common household use, eg. (my own devise) the “Bench and the Bee”.
I propose for the next “arch pub”, as the new-generation pubs are sometimes called, the name “Cup and Frog”. A Thameside location, or indeed along any water, would be apposite.
Note re image: the image shown is drawn from the Wikipedia account referenced above and is used pursuant to the terms of the Creative Commons License No. 4.0 here referenced.