GRAVITY AND 



^University of Cambridge, in a tract which ha 

 has published, with a view of accounting fofr 

 the causfc of gravitation, from mechanical 

 principles ; I shall take the liberty of making the 

 following extracts. 



" KiEPlER supposes that the effect of attraction 

 Is produced by an im material image of the sun, 

 projected from the sun t6 the planet, and draw* 

 ing the planet towards the sun. He says, 

 " Effluxus igitur, quemadmodurn et lcis, im- 

 iriftteriatus est ; non qualis odoriim cum dimi* 

 nutione substaniia?, non qualis 'caloris ab ^estu- 

 ante fornace, et si quid est simile, quibus media 

 implentur. Relinquitur igitur, ut quemadmo- 

 dum lux, omnia terrena illustrans, species est 

 immateriata ignis illius, qui est in corpore solis: 

 ita virtus haec, planetarum corpora complexa 

 et vehen^, sit species immateriata ejus virtutis^ 

 qiiae in ipso sole r^sidet, ineestihiabilis vigoris, 

 adeoqu actus primus omnis motus mun- 

 dani. Videri namque possit in corpore solis 

 latitare divinum quippiam, et comparand urn 

 animse nostrae, ex quo efluat species ista pla-t 

 netas circumagens, uti ex anima jaculantis 

 lapillos species motus in lapillis adhaerescitj 

 qua provehuntur illij etiam cum qui jaculatus 

 est manum ab illis reduxit." ( De Motibus 

 Stella Murtis.)" Etsi igitur species corporis 

 solariis attenuatur in longum et latum, non 

 minus quam lux videtur potius hoc sequen* 



