Shortly after World War II, the Shulsinger Brothers Publishing Company published a beautiful shas. It was the first Shas of such a high caliber published in the U.S. When it became available, Rav Moshe immediately purchased a set. Once, while the Rav was out of the room, a student accidentally knocked over a bottle of blue ink onto one of the volumes. The student was horrified. When Rav Moshe returned and saw the stained gemara, he smiled and commented that blue was his favorite color, and that the Shas looked even more beautiful than before. He then resumed his writing, as if nothing had occurred.