Archimedes Texts

407
trary, the Tide is the cause of them, that is, of bringing them
into the brains more apt for loquacity and ostentation, than for
the speculation and discovering of the more abstruse secrets of
Nature; which kind of people, before they can be brought to
prononnce that wise, ingenious, and modest sentence, I know it
not, suffer to escape from their mouths and pens all manner of ex
travagancies. And the onely observing, that the same Moon, and
the same Sun operate not with their light with their motion, with
great heat, or with temperate, on the lesser reeeptaces of Water,
but that to effect their flowing by heat, they must be reduced to
little lesse than boiling, and in short, we not being able artificially
to imitate any way the motions of the Tide, save only by the mo
tion of the Vessel, ought it not to satisfie every one, that all
the other things alledged, as causes of those essects, are
vaine fancies, and altogether estranged from the Truth. I

say, therefore, that if it be true, that of one effect there is but
one sole primary cause, and that between the cause and effect,
there is a firm and constant connection; it is necessary that when
soever there is seen a firm and constant alteration in the effect,
there be a firm and constant alteration in the cause. And be
cause the alterations that happen in the ebbing and flowing in
several parts of the Year and Moneths, have their periods firm and
constant, it is necessary to say, that a regular alteration in those
same times happeneth in the primary cause of the ebbings and
flowings. And as for the alteration that in those times happens

in the ebbings and flowings consisteth onely in their greatness;
that is, in the Waters rising and falling more or lesse, and in
running with greater or lesse impetus; therefore it is necessary,
that that which is the primary cause of the ebbing and flowing,
doth in those same determinate times increase and diminish its
force. But we have already concluded upon the inequality and
irregularity of the motion of the Vessels containing the Water to
be the primary cause of the ebbings and flowings. Therefore
it is necessary, that that irregularity, from time to time, corre
spondently grow more irregular, that is, grow greater and lesser.
Now it is requisite, that we call to minde, that the irregularity,
that is, the different velocity of the motions of the Vessels, to
wit, of the parts of the Terrestrial Superficies, dependeth on
their moving with a compound motion, resulting from the com
mixtion of the two motions, Annual and Diurnal, proper to the
whole Terrestrial Globe; of which the Diurnal conversion, by
one while adding to, and another while substracting from, the
Annual motion, is that which produceth the irregularity in the
compound motion; so that, in the additions and substractions,
that the Diurnal revolution maketh from the Annual motion,