Space Shuttle related quote referring to a bird on the back of a giant bird

Question

As I look at this amazing picture of the last flight related to the space shuttle taken by Ben Cooper, I am trying to recollect a line from some book (Science or Science fiction) that I read a long time back. It described space flight being imagined as a "Bird on the back of another Giant Bird", or some such words...

Does anyone here recollect the book, author, exact line?
I think it was Arthur C. Clarke but I am not sure and can't find the reference with what I remember.

There are strong connotations to the Virgin Atlantic take-off technique as that line described the idea of taking off from a higher altitude (if my memory serves).

Answer 1

Located in 2001: A Space Odyssey by Arthur C. Clarke
Chapter 7: Space Flight,
Dr. Heywood Floyd recalls a quotation of Leonardo da Vinci's displayed in a NASA office once,

The Great Bird will take its flight on the back of the great bird,
bringing glory to the nest where it was born

Referencing Leonardo da Vinci's Codex on the flight of birds,

The great bird will take its first flight from the back of Monte Cecero,
filling the universe with stupor, filling all writings with its fame and
bringing glory to the nest in which it was born

Other references,

1. Yale University, Leonardo and the Science of Bird Flight (PDF)
2. Decoding da Vinci
   • Drawings from the Biblioteca Real in Turin
     (featuring the Codex on the Flight of Birds and 11 drawings by the artist)