Galilei, Galileo Discorsi 1665, tr. Salusbury, Thomas

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a natural Curiositie, do frequentlie for my Recreation visit that
place, and confer with these persons; which for a certain prehe­

minence that they have above the rest we call ^{*} Overseers: whose
discourse hath oft helped me in the investigation of not only won­
derful, but abstruce, and incredible Effects: and indeed I have been
at a losse sometimes, and despaired to penetrate how that could
possibly come to passe, which far from all expectation my senses
demonstrated to be true; and yet that which not long since that
good Old man told us, is a saying and proposition, though com­

mon enough, yet in my opinion wholly vain, as are many others,
often in the mouths of unskilful persons; introduced by them, as
I suppose, to shew that they understand how to speak something
about that, of which neverthelesse they are incapable.

* Proti.

The Opinion of
Common Artificers
are often false.

SALV. It may be Sir, you speak of that last proposition which
he affirmed, when we desired to understand, why they made

so much greater provision of supporters, and other provisions,
and reinforcements about that Galeasse, which was to be launcht
than is made about lesser Vessels, and he answered us, that they did
so to avoid the peril of breaking its Keel, through the mighty
weight of its vast bulk, an inconvenience to which lesser ships are
not subject.

Great Ships apter
than others to break
their Keels in
Launching, accor­
ding to some.

SAGR. I do intend the same, and chiefly that last conclusion,
which he added to his others, and which I alwaies esteemed a vain
conceit of the Vulgar, namely, That in these and other Machines
we must not argue from the lesse to the greater, because many
Mechanical Inventions take in little, which hold not in great. But
being that all the Reasons of the Mechanicks, have their founda­
tions from Geometry; in which I see not that greatnesse and
smalnesse make Circles, Triangles, Cilinders, Cones, or any other
solid Figures subject to different passions: when the great Ma­
chine is conformed in all its members to the proportions of the
lesse that is useful, and fit for exercise to which it is designed; I
cannot see why it also should not be exempt from the unlucky,
sinister, and destructive accidents that may befall it.

SALV The saying of the Vulgar is absolutely vain, and so
false, that its contrary may be affirmed with equal truth, saying,

That many Machines may be made more perfect in great than lit­
tle: As for instance, a Clock that shews and strikes the Houres,
may be made more exact in one certain size, than in another lesse.
With better ground is that same conclusion usurped by other more
intelligent persons, who refer the cause of such effects in these
great Machines different from what is collected from the pure, and
abstracted Demonstrations of Geometry, to the imperfection of
the matter, which is subject to many alterations, and defects.
But here, I know not whether I may without contracting some