ATD 97-118

Page 99

Hamilton had experienced at Brougham Bridge
William Rowan Hamilton (1805-1865)was an Irish mathematician, physicist, and astronomer who made important contributions to the development of optics, dynamics, and algebra. His discovery of quaternions is perhaps his best known investigation.

The discovery of quaternions reportedly occurred during a walk with his wife by the Royal Canal in Dublin. Upon having the inspiration for the formula, he promptly carved it into the bricks on the side of the canal. Wikipedia entry

Page 109

blindness at the heart of a diamond
This enigmatic imagery is reflected (no pun intended) in a few references:

"where the light came down sifted through so many emerald screens that it was as flawless as the heart of a diamond. " (Anne of Green Gables, Chapt. 15, by Lucy Maud Montgomery)

"It was a singularly sharp night, and clear as the heart of a diamond." A Story that is Untrue by Ambrose Bierce