KORCB. 
yi 
fide, fliey give i!ie following ojiiinon : "It is no longer douht- f •' 
ed, that this force (of percussion) may, wiili perfect truth, ,|„ciriins ot' 
be con.si li ieii as proponiotial, t-iiher to the (juantity of Icrcc, 
matter niuitipliel into the velocity, or to the quantity of 
matter multiplied into the sipiare ol the velocity, acconling to 
the nature of the effect which it isdtvitined to produce*.” 
On the subject of forces, M. I,apl.icc expresses himself as 
follows; “ l.a force pent eire expiimc* par une intinitc lie 
functions de la viiesse, qui n’im[>li()ucnt point contr.adiction. 
II n'y ell n point, par example, a la supposer proporiionnelle au 
c irre pe la \ ilessef.” After slating a h) pothetical example of 
force, where the results would he liitK ii lit Irum those ol ex;;e- 
riepce, hut w here the sipiare of the velocity is I iken in sense 
quite, dilfercnt from that in which it ipp-.ars to have been un- 
derstood by every other .author 1 have had an oppmtuniiy of 
consuliiiig, he proceeds : •• I’auiii leutes Ics fonctions maihc- 
iuaiii|uemeni pos->ibles, examinons quelle est ecMu rte la n.a- 
ture.” And, after reasoning at 'ome length on viiious etfects 
of force, lie coiteludes, “ Voila clone deux lois du mouve- 
inf ut, savoir, la lois (I’iiii'riie ef rdle dc la force propufii.aniellc 
a l.a Vitesse, qui SOI. t (loune.es pat reh'.i rvatioi). b iles soiit les 
plus naturelU's ei les plus simples que run pnisse im.igiiu r, et 
sans douie, elles detivent de la n.atuie meme de la m.aiicre ; 
mats cette nature riant inconmie, ce- lois ne ■•ont pour nous, 
que cles faits observ O', les seuU, au teste, que la n'ceanique 
eniprunte de rcx|>e iencej.” 
It appears, then, to be the opinion of this distingni-hed phi- 
losopher, that, although it m.iy be malliemaiicallv possible for 
the force of a Inxl) in motion to be rroportional to tlie sqn.are 
of its vdocity, yet M’ch .a principle is inconsistent vv iih the 
phenomena of nature ; hut that the law of inertia .and the law 
of force projvirtional to the vehK'ilv, are the most natural and 
the most simple principles imaginahli , that they are derived 
• Kiiiiiijiiidi Review, vol. f.‘, p. t . 0 . 
t .Sysleme dn .Moliilf, 3>l. edit. l.iv. Hi tii. 2. p. 141. 
t Ihid. p. 1 U. 
H 2 
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