1 66 



HISTORY OF SCIENCE. 



FlG. 68. TORRICELLI. 



space in the place of the cause of phenomena which the facts 

 known in his time did not sufficiently explain. He even describes a 

 piece of apparatus by which a vacuum might be produced, and the 

 force necessary to produce it might be measured. A story is told of 

 Galileo in connection with the circumstance of a pump failing to 

 draw water from a well more than 33 feet deep. The details of 

 the incident are differently given by different writers. Sometimes it 

 is the pump-maker, who, when Galileo complained of the pump, 

 informs the philosopher that pumps of the ordinary construction 

 would never draw water from a well of a greater depth than 33 feet ; 

 sometimes it is Galileo that enlightens the well-sinkers. The illus- 

 tration opposite is intended to represent that version of the story 

 which speaks of the workmen of the Grand Duke as having con- 

 structed a well 40 feet in depth, for the ducal palace, and, the lift- 

 pump having failed to raise the water to the surface, Galileo was 

 applied to, when he informed the well-sinkers that this phenomenon 

 was invariable, adding that Nature's abhorrence of a vacuum did not 



