The History of Things 89 



You open the bag and see within it another bag, 

 of a different quality of silk, but very fine. Open 

 that, and lo! a third, which contains a fourth, 

 which contains a fifth, which contains a sixth, 

 which contains a seventh bag, which contains the 

 strongest, roughest, hardest vessel of Chinese clay 

 that you ever beheld. Yet it is not only curious 

 but precious; it may be more than a thousand 

 years old." 



Historical natural science has to do with a sim- 

 ilar process of unwrapping it removes one silken 

 envelope after another, trying to unravel the pat- 

 tern and count the threads and what is finally 

 revealed, though it seem to the careless but as hard 

 clay, is something if we may say something so 

 very old, so very wonderful, that science can give 

 no name to it. 



