Ætat. 19. He invents an Arithmetical Computing Machine

1642.

[190]

Galileo's Investigations of the Atmosphere

[191]

Torricelli pursues this Inquiry

[192]

Father Mersenne explains this matter to Blaise Pascal

[192]

Ætat. 24. Account of Pascal's Discovery of the Atmospheric
Pressure, and his Experiments made on the Puy de Dôme