Tales of Old Japan - Maybe You Like It

Although no one who reads this is likely to put a recipe for blackening
the teeth to a practical test, I append one furnished to me by a fashionable
chemist and druggist in Yedo:—
"Take three pints of water, and, having warmed it, add half a teacupful
of wine. Put into this mixture a quantity of red-hot iron; allow it to stand
for five or six days, when there will be a scum on the top of the mixture,
which should then be poured into a small teacup and placed near a fire.
When it is warm, powdered gallnuts and iron filings should be added to
it, and the whole should be warmed again. The liquid is then painted on
to the teeth by means of a soft feather brush, with more powdered
gallnuts and iron, and, after several applications, the desired colour will
be obtained."
The process is said to be a preservative of the teeth, and I have known
men who were habitual sufferers from toothache to prefer the martyrdom
of ugliness to that of pain, and apply the black colouring when the
paroxysms were severe. One man told me that he experienced immediate
relief by the application, and that so long as he blackened his teeth he
was quite free from pain.
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