82 SIXTEENTH CENTURY. IT. III. 



Galileo's time, so he could not make the experiment very 

 accurately. 



In the year 1592 Galileo established another law in 

 mechanics which is of great value, namely, that any force 

 which will lift a weight of two pounds up one foot will lift a 

 weight of one pound up two feet, or in other words, just as 

 much as you make a weight lighter, so much higher the 

 same force can lift it. If you double the weight, the same 

 force will only lift it half as high ; if you treble the weight, it 

 will only lift it one-third as high, and so on. This law is of 

 immense value in determining the balance of machines, but 

 we cannot examine it further here. At about the same time 

 that Galileo was discovering these laws of motion, a famous 

 engineer, named Stevinus, of Bruges, published a little book, 

 in which he made known some very important laws about 

 the rest and motion of bodies, which formed the foundation 

 of the modern science of statics, or the study of bodies at 

 rest. 



Summary of the Science of the Sixteenth Century .- 

 And now we must pause for a moment in the history of 

 Galileo, for his astronomical discoveries belong to the next 

 century, and before entering upon them we must reckon 

 up the advances which had been made in science during 

 the past hundred years. 



I think you will agree with me that at least one grand step 

 had been made when men learned to examine for themselves, 

 and were no longer content merely to repeat like parrots what 

 the Greeks had handed down to them. Copernicus had 

 shown in astronomy, Vesalius in anatomy, and Galileo in 

 mechanics, that it was no longer enough to quote passages 

 from Ptolemy, Galen, and Aristotle ; but men must take the 

 trouble to examine the works of nature for themselves, if 



