Archimedes Texts

135
velocity, no imaginable diversity could be found either in this,
or any other experiment whatsoever, as I am anon to tell you.
Now if in this case there appeareth no difference at all, what can
be pretended to be seen in the stone falling from the top of the
Tower, where the motion in gyration is not adventitious, and ac
cidental, but natural and eternal; and where the air exactly fol
loweth the motion of the Tower, and the Tower that of the Ter
restrial Globe? have you any thing else to say, Simplicius, upon
this particular?

SIMP. No more but this, that I see not the mobility of the
Earth as yet proved.

SALV. Nor have I any intention at this time, but onely to
shew, that nothing can be concluded from the experiments alledg
ed by our adversaries for convincing Arguments: as I think I
shall prove the others to be.

SAGR. I beseech you, Salviatus, before you proceed any far
ther, to permit me to start certain questions, which have been
rouling in my fancy all the while that you with so much patience
and equanimity, was minutely explaining to Simplicius the expe
riment of the Ship.

SALV. We are here met with a purpose to dispute, and it's fit
that every one should move the difficulties that he meets withall,
for this is the way to come to the knowledg of the truth.
Therefore speak freely.

SAGR. If it be true, that the impetus wherewith the ship moves,
doth remain indelibly impress'd in the stone, after it is let fall from
the Mast; and if it be farther true, that this motion brings no im
pediment or retardment to the motion directly downwards, na
tural to the stone: it's necessary, that there do an effect ensue of

a very wonderful nature. Let a Ship be supposed to stand still,
and let the time of the falling of a stone from the Masts Round-top
to the ground, be two beats of the pulse; let the Ship afterwards
be under sail, and let the same stone depart from the same place,
and it, according to what hath been premised, shall still take up
the time of two pulses in its fall, in which time the ship will have
run, suppose, twenty yards; To that the true motion of the stone
will be a transverse line, considerably longer than the first straight
and perpendicular line, which is the length of the ^{*} Mast, and yet

nevertheless the ^{*} stone will have past it in the same time. Let
it be farther supposed, that the Ships motion is much more accele
rated, so that the stone in falling shall be to pass a transverse line
much longer than the other; and in sum, increasing the Ships ve

locity as much as you will, the falling stone shall describe its trans
verse lines still longer and longer, and yet shall pass them all in
those self same two pulses. And in this fashion, if a Canon were