What number was the Tironian note visually similar to?
The Latin alphabet of the time still lacked the letters ⟨j⟩ and ⟨w⟩, and there was no ⟨v⟩ as distinct from ⟨u⟩; moreover native Old English spellings did not use ⟨k⟩, ⟨q⟩ or ⟨z⟩.