The Modern Bartenders' Guide by O. H. Byron (1884, p.9)

1Absinthe — Source says one pony glass absinthe.base
water — Added to the bowl and allowed to drip until the color shows a sufficiency.dilution
ice — fine iceother
  1. Pour the absinthe into the absinthe glass.
  2. Fill the bowl with fine ice and the balance with water, then elevate the bowl and let the contents drip into the absinthe until the color is sufficient.
  3. Pour into a large bar glass and serve.

Ice: Fine ice