76 PIONEERS OF EVOLUTION PART 



strange, although it is, perhaps, partly explained 

 by the fact that his writings were not reissued for 

 more than three centuries after his death. He has 

 been credited with a number of inventions, his title 

 to which is however doubtful, although the doubt in 

 nowise impairs the greatness of his name. He 

 shared the current belief in alchemy, but made a 

 number of experiments in chemistry pointing to his 

 knowledge of the properties of the various gases, 

 and of the components of gunpowder. If he did 

 not invent spectacles, or the microscope and tele- 

 scope, he was skilled in optics, and knew the 

 principles on which those instruments are made, 

 as the following extract from his Opus Majus shows. 

 'We can place transparent bodies in such a form 

 and position between our eyes and other objects 

 that the rays shall be refracted and bent towards 

 any place we please, so that we shall see the object 

 near at hand, or at a distance, under any angle we 

 please ; and thus from an incredible distance we may 

 read the smallest letters, and may number the smallest 

 particles of sand, by reason of the greatness of the 

 angle under which they appear.' He knew the 

 ' wisdom of the ancients ' in the cataloguing of the 

 stars, and suggested a reform of the calendar 

 following the then unknown poet- astronomer of 

 Naishapur. But he believed in astrology, that 

 bastard science which from remotest times had ruled 

 the life of man, and which has no small number of 

 votaries among ourselves to this day. Roger Bacon's 

 abiding title to fame rests, however, on his insistence 

 on the necessity of experiment, and his enforcement 

 of this precept by practice. As a mathematician he 



