396 THE INTELLECTUAL RISE IN ELECTRICITY. 



Monconys says that Guericke told him, among other 

 things, that the smooth yellow sphere which was exhibited 

 was made of nine different minerals, but either Monconys' 

 memory was at fault or else Guericke thought a little mis- 

 direction justifiable in the circumstances. Guericke him- 

 self tells how to make the globe, as follows: "Take a 

 sphere of glass (called a vial) of about the size of the 

 head of an infant; put in it sulphur that has been pulver- 

 ized in a mortar, and sufficiently liquefied by being placed 

 near a fire. When this has become cool, break the sphere, 

 take out the globe, and keep it in a place that is dry." 

 Afterwards it is to be perforated, so that it can be rotated 

 on an iron axis, and that, perhaps, is a reason why he did 

 not rub the glass vial itself instead of the sulphur cast in 

 it. It would be difficult to make a smooth round hole in 

 the imperfect glass of those days, for the insertion of the 

 axis. 



The sulphur globe being described, Guericke proceeds 

 to show how it possesses the different virtues and the re- 

 sults thereof. 



"It Has, first, the impulsive virtue (momentum), because, 

 being heavy, it can be hurled by the hand further than if 

 it were made of wood or lighter material." So also it has 

 the conservative virtue, to exhibit which the axis of the 

 globe is placed in two supports a hand's breadth above the 

 supporting base or platform, upon which and beneath the 

 globe are to be strewn "all sorts of little fragments, like 

 leaves of gold, silver, paper, shavings," etc. The direc- 

 tions are to "stroke the globe with the dry palm, so that 

 it may be rubbed or submitted to friction thus twice or 

 thrice. Then it will attract the fragments, and when 

 turned on its axis will take them along with itself. In 

 this manner is placed before the eye the terrestrial globe, 

 as it were, which by attracting all animals and other things 

 which are on its surface, sustains them and takes them 

 around with itself in its diurnal motion in twenty-four 

 hours. 



