Shama-il Tirmidhi Chapter 007, Hadith Number 004 (051).

Ibn 'Abbaas Radiyallahu 'Anhu says: "Rasulullah Sallallah 'Alayhi Wasallam has said: 'The best from among all the kuhl used by you is the one made from ithmid. It brightens the eyesight and strengthens the growth of the eye lashes"'.

Commentary.
One of the narrators in the chain of this hadith is Bishr bin Mufaddal RA. The 'ulama wrote that he performed four hundred rak'ahs nafl daily, and it was his permanent practice to fast every alternate day.