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8 Degrees, and 12 from 4, after Reflexion it was 
driven up again to 4, as before. 
. EXPERIMENT IX. 
The Ball 5 falling from fixteen Degrees met the 
Ball iz that fell dill from 4, and after Reflection iz 
went up again to 4. 
EXPERIMENT X. 
The Ball z falling from 6 ^ and iz from i®, iz was 
reflected to i, and when z fell from iz Degrees, and 
the Ball iz from 2, the 12 was reflected to 2. 
EXPERIMENT XI. 
The Ball of eight Penny Weight (which weigh’d 
but 3 4 of the Ball 12) falling from fifteen Inches or De- 
grees, rais’d up 12 (that fell from half a Degree) to the 
lame Place again. 
In all thele Experiments the Error, or want of per- 
fect Reflection, was greater in the little Balls than in 
the great ones, on account of their going thro’ a grea- 
ter ^rc of a Circle, whereby they deviated more 
from a Cycloid than the great ones ; as likewiie on 
Account of the Refiftance of the Air, which muO: 
be greater becaufe of the little Balls going through a 
greater moving with more Velocity, being llif 
pended by a String as thick as that of the great ones, 
and having more Surface in Proportion to their Weight. 
But all the Errors do not bring the ^hanomena any 
thing near what they ought to be,iftheForce ofthe Bo- 
dies was as the Square of their Velocities multiply’d in- 
to their MalTes, for then the Ball 12 would have been 
driven to Heights very different from what it rofe up to. 
X X In 
