The Riddle of the Sphinx

One of our agents found a shred of parchment in an antiques dealer in Cairo. Faintly legible, the following may shed some light on Project Pegasus.

One day, Ozymandias was traveling in the desert. He came across a statue, long since worn almost to dust. At its base read the words, “God Save the Queen.”

Ozymandias thought this was an odd thing and carried on his way.

Soon after, he came to a large crevasse. Guarding the path across was the very Sphinx, itself.

“Halt!” cried the Sphinx, its terrible claws drawing sparks from the desert stone, “I will not let you pass unless you answer my riddle.”

Being the wisest king of all the lands, whose feats would be known forever across the sands of time, Ozymandias replied that he was not afraid and that he would answer the riddle.

“Fail to answer correctly, and I will throw you to your death,” warned the Sphinx.

Knowing that his mind had never failed him before, Ozymandias bid the Sphinx to continue.

“What is zero in the morning, full of numbers in the afternoon, and infinity in the night?” asked the Sphinx.

With a smile, Ozymandias told the Sphinx the correct answer. He passed by the Sphinx and over the crevasse, to continue his journey on into the history books.

What did he say?