THE MICROSCOPE: CHARLES SINGER 



55 



point of the sun, and one only falls perpendicularly on the flask, 

 all the others are refracted and meet at one point on the perpen- 

 dicular ray which is given off along with them from the sun, and 

 this point is the point of combustion, because on it are collected 

 an infinite number of rays, and the concentration of light causes 

 combustion. But this concentration would not take place except 

 by double refraction, as shown in the diagram." (Opus Mains y 

 Part VII). 



Glasses (per spicy a) can be so constructed that objects at a 

 very great distance appear to be quite close at hand, and conversely. 

 Thus we read the smallest letters from an incredible distance, number 

 objects, however small, and make the stars appear as near as we 

 wish. . . , Also objects can be made to appear so that the 



FIG 3. 



greatest seems the least, and conversely; what are high appear low 

 and short, and conversely ; and what is hidden appears manifest. . . 



But among the more subtle powers of construction is this of 

 directing and concentrating rays by ^means of (instruments of) 

 different forms and reflections at any distance we wish, where what- 

 ever is subjected to them is burned. . . . But greater than 

 any such design or purpose is that the heavens might be portrayed 

 in all their length and breadth on a corporeal figure moving with 

 their diurnal motion, and this would be worth a whole kingdom to 

 a wise man. Let this, then, be sufficient as an example, although 

 an infinite number of other marvels could be set forth." (De 

 Secretis Operihus Artis et Naturae.) 



It is a remarkable thing that no complete edition of the works 

 of Roger Bacon has ever been prepared, nor any important work 

 by him translated into English. The above passages I have trans- 

 lated from J. H. Bridges, The Opus Majus of Rogerh Bacon, Oxford, 

 1897, and J. S. Brewer, Fratris Roger Bacon opera quaedam hactenust 

 inedita, London, 1859. 



