“A circle is a round straight line with a hole in the middle.”
Mark Twain (1835–1910) American author and humorist
Quoting a schoolchild in "English as She Is Taught"
The Notebooks of Leonardo da Vinci (1883), II Linear Perspective
“A circle is a round straight line with a hole in the middle.”
Mark Twain (1835–1910) American author and humorist
Quoting a schoolchild in "English as She Is Taught"
Leonardo Da Vinci (1452–1519) Italian Renaissance polymath
The Notebooks of Leonardo da Vinci (1883), II Linear Perspective
Joseph von Fraunhofer (1787–1826) German optical physicist
Prismatic and Diffraction Spectra: Memoirs http://books.google.com/books?id=5GE3AAAAMAAJ (1899) Tr. & Ed. J. S. Ames p. 7
Leonardo Da Vinci (1452–1519) Italian Renaissance polymath
The Notebooks of Leonardo da Vinci (1883), II Linear Perspective
Karel Appel (1921–2006) Dutch painter, sculptor, and poet
in 'The eye of the beholder', Carlo McCormick
Karel Appel – the complete sculptures,' (1990) not-paged
Leonardo Da Vinci (1452–1519) Italian Renaissance polymath
The Notebooks of Leonardo da Vinci (1883), III Six books on Light and Shade
Leonardo Da Vinci (1452–1519) Italian Renaissance polymath
The Notebooks of Leonardo da Vinci (1883), III Six books on Light and Shade