ASTRONOMICAL HISTORY. 181 



ject from experience, and presently turning away in a sort 

 of scorn from nature, at once pusillanimous and audacious. 

 Of that however we shall presently speak, when we come 

 to the question, &quot; whether the stars are real fires,&quot; and more 

 largely and correctly in our counsels respecting the History 

 of Virtues, where we shall discourse of the sources, and 

 cradles of heat and cold, as yet unknown to and untouched 

 by man. Thus we have stated the question with respect 

 to the heterogeny of the heavenly bodies. For though, 

 perhaps, the case demands that we should condemn, with 

 out postponing the conviction, the doctrine of Aristotle, it 

 is not consistent with our purpose. 



Another question proposed was, what that substance 

 is contained in the interstellar spaces ? These are either a 

 void as Gilbertus conceived; or filled with a substance, 

 which is to the stars what air is to flame, the hypothesis 

 most closely approaching the experience of our senses ; or 

 filled with a substance essentially the same with that of 

 the stars themselves, luminous, and to a certain degree em 

 pyrean, but of a secondary order, being of a light not so 

 brilliant and coruscating, which seems to be meant by the 

 received opinion that a star is the denser part of its own 

 sphere. For there can be no objection to conceiving it a 

 bright transparent medium, for conveying stronger light. 

 Telesius has acutely observed, that common air contains 

 within itself a certain quantity of light, using this argu 

 ment, that there are certain animals which see by night, 

 whose visual organs are adapted to receive and kindly 

 entertain this weak sort of light. For it is a less credible 

 supposition that a visual act takes place without any light, 

 or from the internal illuminating power of the spirit. And 

 even flame itself is seen diaphanous, to such a degree as 

 to give out the form of opaque substances, as is seen in 

 the wick of candles, much more to be the vehicle for the 

 form of more intense light. For the flame of tallow or 

 wax is more lustrous, and, if we may use the expression, 

 more igneous; but the flame of spirits of wine is more 

 opaque, and as it were more aeriform, so that the flame is 

 not inspissated. And I also made an experiment on this 

 subject, which was done by taking a wax candle and 

 raising it in a sconce, (using a metal one for the purpose of 

 protecting the body of the candle from the flame, which 

 was to be circu infused), and placing the sconce in a goblet 

 in which was a small quantity of spirits of wine, and first 

 lighting the candle, and then igniting the spirits of wine; 



