33 



usque ceiilrn soüs et plunclnrum , sine virlulis dimiiiutiuiic ; 

 quacqiie agil noii pro quaiitilate siiperücioruni parliciilarun:, in 

 qiias agil (ut soleiil causae mechanicac), scd pro qiiaiililalc iiia- 

 leriac solidae. — Kalionem harum gravitatis proprielaltim ex 

 phacnoinenis nondum poUii deducere el hypolhescs non Hugo. 

 Satis csl quod gravilas revera exislat et agat secuiidum Icges a 

 nobis expositas. 9tetVton, Principia Phil. nat. p. 676. — 

 l'o lell US lliat evciy species ot' Ihings is endow'd wilh an occull 

 jpcciück qunlily by Avhich il acts and produccs manifest etl'ccls. 

 is lo teil US nolhing: bul to derive Iwo or ihree gcneral prin- 

 ci[)les of motion from phaenomena, and aiterwards lo leli us how 

 Ibe propcrlics and aclions of all corporeal Ihings foUow from 

 Ihose manifest principics, would bc a very great Step in lUiilo- 

 sophy, though Iho causes of ibose principics were not yel dis- 

 covered : and therefore I scruplc not to propose the principics of 

 motion and leavc Uieir causes lo be found out. ^teivton,. 

 Opticks p. 377. gnil)er, Query 31 p. 351, Ijei^t eö: JJodies 

 act one upou anolhcr by ihe attraction of gravily, magnelism 

 and eleclricily, and it is not improbable ihat Ihere may be niore 

 attractive powers than thcse. How these attractions may bc per- 

 formed, I do not here consider. What I call atlraclion, may be 

 performed by impulse or by some olher means unknown lo me. 

 i use Ihal word here lo signify only in general any force by which 

 bodies tend lowaids onc anolher, whatsoever be Ihe cause. 



*' (@. 23.) I suppose the rarer aclher within bodies and 

 the denser without them. Oper um Newtoni Tomus IV. (ed. 

 1782 ©am. J>>r^lei)) p. 386, mir Qdituenbuuä auf bte erflärunc} 

 ber »ou ©rimalbi eittbecften 2)it|ractiou ober 2tcl)tbeii3ung. 'Jim 

 ©c^duiTe beö 23riefeö von 9(eivton an i)iobert 33oi)[e vom Jebr. 1678 

 p. 394 l)ei^t e6: I shall set down onc conjecture more which came 



info my mind: il is about the cause of gravily Sind) bie 



Sorrefponbenj mir Clbeuburg »om 2>ecember 1675 beiuei(t, t)a^ 

 bet gro^e 9)?ann bamalö Inen 'Jlet{)cx : S?\)\>oti)e[e\x nidjr abäenetgr 

 war. 9tad? biefen fodte ber ©top beei materiellen Sid}te^ bew 

 ''3{etl)er in ©cfjroingung \et}e\x; bie ©ttwinqunijcn beö 3Iet()er^ allein, 

 welcher 23erwrtnbtt'd)aft mit einem ^'a-rüen-Slutbum l)at, erieugren 

 ttic^t btt^ 2id)t. @, über ben ©treir mir .^oofe jj>or^lei) T. IV 

 p. 378 - 380. 



51 ü. .^iimbolbt, Äojiiio« III 3 



