I"] 
from the height of half the length of the Pendukm^ as the 
Cirmmfereme 2^ Circle to its Diameter ; whence as a Corol^ 
/^r^ it follows, that as t\iQ Square of the Diameter to tha 
Square of the Circumference^ fb half the length of the Ven^ 
Mum vihvditmg feconds^ to th.t /pace defcribed by the fall of a 
My in a fecord of time : and the length of the Pendulum vi- 
brzting fecondsy being found 59,125501* i Inches, the defeat in 
3, fecond Will be found by the aforeiaid Amlogy 1 6 Fpot and one 
Jnch : and by the third Propofition , the Velocity will be 
double thereto ; and near to this it hath been found by ft- 
veral Experiments^ which by realbn of the fmftnefio? the faH^ 
cannot fb exadly determine its quantity. The Demonftra- 
tion dt Hugenim being the Conclufion or a long train of Con- 
I fliaU for brevity fe^^ omit ; and refer you to his 
Book, where theft things are niore amply treated of 
From theft iQvx Propjitimsy all j^f/zc?;^/ concerning the 
Perpindicularfallpf hodieSy2LVQ eafily folved^ and eitlier 77/^<f, 
Hdghty QvVelccity h€mg%f[tgnQA^ one may readily find the 
other two. From them likewift is the Do£lrine of Projects 
deduciblei, alTuming the two following Axioms \ That a 
body ftta moving, will move pn continually in a right line 
with an equable motion^^^nnhrs fbmc other force or impediment 
intervene, whereby it is accelerated ^ or retarded , or de- 
fie£ted. - r : 
Secv/sdlyyThz.tSi Body being agitated by two motions at a 
time, does by their c^mfomded forces pafi through the fame 
fointSy as it would do, were the two motions divided and act- 
ed fucceffively. As for inftance, Suppofe a body moved in the 
Line GF, F/^^2.rAi.) froni G to R, and there ftopping, 
by another impulfe fiippofe it moved in a Jpace oitime equal to 
the former, from R towards K, to V. I lay, the body ^hiW 
pais through the point V, tho' theft t wo fever al force s^ afted 
botliin they^^ f/^^f. ; 
Prof. V. The Motion of all PrcjeMsis in t\iQ Curve of a Pa- 
rahola : Let the Ime GRF ('m fig- ^J hQ th(^^linem which the 
Projetl is direded, and in which by ^the firft Axiom it would 
B move 
