Alas! Your dear friend and servant Galileo has been for the last month hopelessly blind; so that this heaven, this earth, this universe, which I by my marvelous discoveries and clear demonstrations had enlarged a hundred thousand times beyond the belief of the wise men of bygone ages, henceforward for me is shrunk into such a small space as is filled by my own bodily sensations. Jan. 2, 1638, The private life of Galileo, pp.278-279.

I have been in my bed for five weeks, oppressed with weakness and other infirmities from which my age, seventy four years, permits me not to hope release. Adde…

Allan-Olney, Mary. The private Life of Galileo: Compiled primarily from his correspondence and that of his eldest daughter, Sister Maria Celeste, (nun in the F…

...if I shall have sufficient strength to improve and amplify what was written and published by me up to now about motion by adding some little speculations, a…

'The more original a discovery, the more obvious it seems afterward.'

A great chapter of the history of the world is written in the chalk. Few passages in the history of man can be supported by such an overwhelming mass of direct…

Although the problem of transmuting chemical elements into each other is much older than a satisfactory definition of the very concept of chemical element, it …