10 THEORY OF THE FIRMAMENT. 



these we have said are not cosmical, but reciprocal. There 

 are four kinds of motions visible in the heavens, besides that 

 which we have called cosmical, which is a diurnal motion in 

 curves within the tropics. For either the stars are raised 

 higher, and again depressed lower, as they may be farther 

 from and nearer to the earth ; or they bend and wind them 

 selves through the latitude of the Zodiac, by running out 

 more to the south, or more to the north, and by traversing 

 what they call the dragons ;* or they vary from an incited 

 and also an acquisitive motion -f- (for we join together these 

 two), advancing sometimes quicker, sometimes slower, 

 sometimes progressively, sometimes retrogressively, some 

 times even stopping and staying ; or at a certain distance 

 from the sun, they are more or less bound together and 

 drawn round each other. We will recount the causes and 

 natures of these only, generally touching the heads of each; 

 for our present undertaking requires that to be done in this 

 place. But in order to this, and to secure beforehand, as 

 well as to open the way, we must frankly declare our sen 

 timents upon some of the maxims of philosophers, as also 

 upon certain hypotheses of astronomers, as well as their 

 observations during several ages, out of which materials 

 they built up their mysteries ; all which things appear to 

 us to be full of error and confusion. Wherefore there are 

 axioms, or rather certain conceits, which, received by phi 

 losophers, and transferred to astronomy, and unfortunately 

 being credited, have corrupted the science. Our rejection 

 of them will be simple, as well as our judgment upon them; 

 for it is not suitable to waste precious time on silly refuta 

 tions. The first of these is, that all things above the moon 

 inclusively are incorruptible; and in no degree or form 

 whatever do they undergo new beginnings or changes ; of 

 which it has been said elsewhere, that it is a fond and silly 

 saying. Indeed, from this source proceeds that prodigious 

 evil, that, on the appearance of every irregularity astro- 



* The twelve signs of the Zodiac, I presume ; so called, because most of them 

 resemble some living creature ; thus Eurip. in Oreste has Apa/covrax^jjc, &quot;dra- 

 conibus, seu anguibus plenus;&quot; or it may mean the two Nodes, which comes to 

 the same thing, represented by the head and the tail of the Dragon ; for the as 

 cending Node and Dragon s head have the same character to denote each () ; 

 so likewise the descending Node and Dragon s tail ($ ). 



t Consecution, used by Newton ; does it mean &quot; picked up on its revolution,&quot; 

 or an orderly accompanying, &c. ; a relative motion; or a train of consequential 

 .motion, inritatio referring to original ? 



