1^4 ^ ^iotatlon rej^ditttg the Figure ef the Earth, ^e, 



IX. 



On the Ktioivledge of the Ancients refpeBing Gravity. By a Ctrrefpondent. 



JL H E refpedable publifliers of the " Journal of Natural Philofophy, Chemiftry and th« 

 Arts," are defired to fubmit to the infpedlion of its ingenious Author the following obfer- 

 vations relative to a Note at page 85 of the 15th Number. ( Vol. II.) 



" In the treatife of * Plutarch De Placitls Philofophorum,' occurs no paflage referring to 

 the 'vibration of a body through the centre of the earth to the antipodes, and to the reten- 

 tion of the moon in its orbit by the combination of the proje£iiIe and gravitating forces.' " 



The paffage alluded to is probably in the treatife " De Facie qua; in Orbe Luna: ap- 

 paret ;" but there, fo far from proving a gravitating force, the abfurdity of the fuppofition is 

 endeavoured to be {hewn. 



Ed. Oxon. — 8vo. T. iv. § ^. ^iroo-of i;v Jf «« auxriov, av ra isa^a^o^a, wafaSbloi; aixuvtaiai ffn- 



STOi TW cm TO /JLCffOV fo^av eivaysa-tv. 'H, ri -aa^a^a^ov kk ivsrtv ; Ouxt Ttir yw (7(paioay tivai, thAi- 

 fiavTct ^aBv) Hat yj'i *'" ava%a>.t!c; sxs-rav ; OuK avTiwoJitf omeiv, auTtz^ ^^iTraf, jj yaXeccTa;, rpaTTivrct 

 ava ra xara t»i tji 'EpohxoiJ''i"^i j "i^as ^e aulni /in wf 0; o^6a( ^iStixola;, aA^a wPiayiOi/; cpri/xemv 

 aTTOvBvovTai, UTinq 01 fxs6vovTis ; Ou /xi/Sjrsj x'^"'''«^«'''?«5 ^'« ^aflsf tds />){ ^e^ofisvs;, olav tiixavlcH 

 ispoi TO jMEiroy, iratirflai /xri^evoi aTtavru^o;, //.noc vTrepiioovroi j Ei Si f u^ttw kutoj (pt^ojAivai to /x^jov uttcp- 

 Cax^ouv, ai/foj o%icra rfEf £o-9«i kcu avaxa//,'xlciv wtt' avlm. Thus tranflated by Philemon Hol- 

 land — " But we ought not to give ear unto philofophers, if they would maintain flrange 

 " paradoxes by other pofitions as abfurd, or, to confute admirable opinions, devife others 

 " much more extravagant and wonderful, like as thefe here who broach and bring in a 

 " notion, forfooth, tending unto a middle, wherein, what abfurdity is there not ? Hold 

 •« not they that the earth is as round as a ball, and yet we fee how many deep profundities, 

 " haughty fublimities and manifold inequalities it hath ? Affirm not they that there be an- 

 ** tipodes dwelling oppofite one unto another, and thofe flicking as it were to the fides of the 

 •' earth with their heels upward and their head downwards topfy turvy, like unto thefe wood- 

 *' worms or cats (r. newts) which hang by their (harp claws? Would not they have even us alfo 

 *' that are here, for to go upon th? ground not plumb upright, but bending or inclining fide- 

 " long, reeling and flaggering like drunken folk ? Do they not tell us tales, and would make 

 *' us believe, that if bars and mafles of iron weighing a thoufand talents a piece were let fail 

 " down into the bottom of the earth, when they came once to the middle centre thereof, 

 *' will ftay and reft there, albeit nothing elfe came againft them nor fuftained them up ? And 

 ** if peradventure by fome forcible violence they fliould pafs beyond the faid midft, they 

 •' would foon rebound back thither again of their own accord?" 



So true is the obfervation of Cleomedes, that thofe among the ancients who treated of 

 natural philofophy were much confufed, and on this head greatly erred, not beino- able to 

 difcern, that fince the world was of a fpherical figure, the centre muft of ncceffity be inferior 



to every part of it — ai h XoiTrai crx^o-c 'TrofAw ■7rape(rxov Tapaxw Toif va)\aioTcpoi; rav ^ua-ixav ou 



SuvJi^EvToiv ETTirtia'ai, oti ev tm xoirfM, ^(pMpixa ra (^xnixstri ovli, x»ra /xcv uTto wwlof aum, to fica-analov 

 tivcci amyxouov. De Meteoris, ed. Balforei, 1605, p. 9. 



Rtmarki 



