<s><margin.target id="marg345"></margin.target><emph type="italics"/>Projects conti <lb/>
nue their motion <lb/>
by the right line <lb/>
that followeth the <lb/>
direction of the <lb/>
motion, made to <lb/>
gether with the <lb/>
projicient, whil'&longs;t <lb/>
they were conjoin'd <lb/>
therewith.<emph.end type="italics"/></s>

<s>SIMP. </s><s>So it is, in my opinion.</s>

<s>SAGR. </s><s>Now imagine the cylinder to be erected, and that the <lb/>
Earth doth revolve about with a diurnal motion, carrying the <lb/>
piece along with it, tell me what &longs;hall be the motion of the ball <lb/>
within the cylinder, having given fire?</s>

<s>SIMP. </s><s>It &longs;hall be a &longs;treight and perpendicular motion, the cylin <lb/>
der being erected perpendicularly.</s>

<s>SAGR. </s><s>Con&longs;ider well what you &longs;ay: for I believe that it will <lb/>
not be perpendicular. </s><s>It would indeed be perpendicular, if the <lb/>
Earth &longs;tood &longs;till, for &longs;o the ball would have no other motion but <lb/>
that proceeding from the fire. </s><s>But in ca&longs;e the Earth turns round, <lb/>
<arrow.to.target n="marg346"></arrow.to.target> <lb/>
the ball that is in the piece, hath likewi&longs;e a diurnal motion, &longs;o <lb/>
that there being added to the &longs;ame the impul&longs;e of the fire, it mo <lb/>
veth from the breech of the piece to the muzzle with two motions, <lb/>
from the compo&longs;ition whereof it cometh to pa&longs;&longs;e that the motion <lb/>
made by the centre of the balls gravity is an inclining line. </s><s>And <lb/>
for your clearer under&longs;tanding the &longs;ame, let the piece A C [<emph type="italics"/>in <lb/>
Fig.<emph.end type="italics"/> 2.] be erected, and in it the ball B; it is manife&longs;t, that the <lb/>
piece &longs;tanding immoveable, and fire being given to it, the ball <lb/>
will make its way out by the mouth A, and with its centre, pa&longs; <lb/>
&longs;ing thorow the the piece, &longs;hall have de&longs;cribed the perpendicular <lb/>
line B A, and it &longs;hall pur&longs;ue that rectitude when it is out of the <lb/>
piece, moving toward the Zenith. </s><s>But in ca&longs;e the Earth &longs;hould <lb/>
move round, and con&longs;equently carry the piece along with it, in <lb/>
the time that the ball driven out of the piece &longs;hall move along <lb/>
the cylinder, the piece being carried by the Earth, &longs;hall pa&longs;&longs;e in <lb/>
to the &longs;ituation D E, and the ball B, in going off, would be at <lb/>
the corni&longs;h D, and the motion of the bals centre, would have <lb/>
been according to the line B D, no longer perpendicular, but in <lb/>
clining towards the Ea&longs;t; and the ball (as hath been concluded) <lb/>
being to continue its motion through the air, according to the <lb/>
direction of the motion made in the piece, the &longs;aid motion &longs;hall <lb/>
continue on according to the inclination of the line B D, and &longs;o <lb/>
&longs;hall no longer be perpendicular, but inclined towards the Ea&longs;t, <lb/>
to which part the piece doth al&longs;o move; whereupon the ball may <lb/>
follow the motion of the Eerth, and of the piece. </s><s>Now <emph type="italics"/>Simplicius,<emph.end type="italics"/> <lb/>
you &longs;ee it demon&longs;trated, that the Range which you took to be <lb/>
perpendicular, is not &longs;o.</s>

<s><margin.target id="marg346"></margin.target><emph type="italics"/>The revolution <lb/>
of the Earth &longs;up <lb/>
po&longs;ed, the ball in <lb/>
the piece erected <lb/>
perpendicularly, <lb/>
doth not move by a <lb/>
perpendicular, but <lb/>
an inclined line.<emph.end type="italics"/></s>

<s>SIMP. </s><s>I do not very well under&longs;tand this bu&longs;ine&longs;s; do you, <lb/>
<emph type="italics"/>Salviatus<emph.end type="italics"/>?</s>

<s>SALV. </s><s>I apprehend it in part; but I have a certain kind of <lb/>
&longs;cruple, which I wi&longs;h I knew how to expre&longs;s. </s><s>It &longs;eems to me, that <lb/>
according to what hath been &longs;aid, if the Piece be erected perpen <lb/>
dicular, and the Earth do move, the ball would not be to fall, as <lb/>
<emph type="italics"/>Ari&longs;totle<emph.end type="italics"/> and <emph type="italics"/>Tycho<emph.end type="italics"/> will have it, far from the Piece towards the