ASTRONOMICAL HISTORY. 185 



and has not a conspicuous magnitude, and an intense, 

 strong light, escapes the eye, and makes no difference in 

 the face of heaven. Nor let it strike doubt into the mind 

 of any less informed inquirer, if the question suggests it 

 self, whether globes of consolidated matter can remain pen 

 sile ? For the earth itself floats pensile in the midst of its 

 circumambient air, the softest of substances, and huge 

 volumes of watery clouds and magazines of hail are long- 

 suspended in the fields of air, and are rather precipitated 

 than spontaneously descend, before they begin to be affected 

 by the earth s contiguity. Wherefore Gilbertus has very 

 well noted that heavy bodies, when carried to long distances 

 from the earth, are gradually divested of their motion to 

 wards the objects beneath, arising from no other propen- 

 sion of bodies, than that of uniting and conglomerating to 

 the earth (which is a collection of homogeneous substances), 

 and of which the influence terminates with its own sphere. 

 For as to what is asserted of a motion to the earth s centre, 

 that would be a sort of potent nothing dragging to itself 

 such large masses ; whereas body cannot be affected except 

 by body. Wherefore let this inquiry concerning solid and 

 opaque globes, although it appear new, and to common appre 

 hension difficult, be entertained ; and let another be asso 

 ciated with it, the old and undecided one, which of the 

 stars give forth a light original and from themselves, and 

 which from the illumination of the sun ; the one class ap 

 pearing to be connatural to the sun, and the other to the 

 moon. 



Finally, we understand all investigation concerning the 

 difference of substance among the stars relatively to one 

 another, a multifarious subject, as it seems, since some 

 are red, some leaden, some white, some manifestly always 

 brilliant, others nebulous, to refer to our seventh query. 

 It is another question, whether the stars are real fires, 

 which question notwithstanding requires a degree of con 

 sideration rightly to comprehend it. For it is one thing to 

 say, that the stars are real fires, and another that the stars, 

 supposing them to be real fires, exercise all the properties 

 and perform all the effects of common fire. Not that we 

 are, therefore, to have recourse to the idea of an abstract 

 and imaginary fire retaining the name of fire, but rejecting 

 its properties. For our fire, if placed in ether in such a 

 quantity, as the quantity composing a star, would perform 

 different operations from those which are observed on 

 earth ; since things acquire far different properties, both 



