1with water, as ſoon as its ſuperiour Superficies, before vailed with
water, doth arrive to the Levell of the univerſall Surface of the ſaid
water. To ſay, in the next place, that water can encreaſe the weight
of things that are demitted into it, is moſt falſe, for water hath no
Gravity in water, ſince it deſcends not: yea, if we would well
der what any immenſe Maſs of water doth put upon a grave Body;
that is placed in it, we ſhall find experimentally, that it, on the
trary, will rather in a great part deminiſh the weight of it, and that
we may be able to lift an huge Stone from the Bottom of the water,
which the water being removed, we are not able to ſtir. Nor let
them tell me by way of reply, that although the ſuperpoſed water
augment not the Gravity of things that are in it, yet it increaſeth the
ponderoſity of thoſe that ſwim, and are part in the water and part
in the Air, as is ſeen, for Example, in a Braſs Ketle, which whilſt it
is empty of water, and repleniſhed only with Air ſhall ſwim, but
pouring of Water therein, it ſhall become ſo grave, that it ſhall ſink
to the Bottom, and that by reaſon of the new weight added thereto.
To this I will return anſwer, as above, that the Gravity of the
Water, contained in the Veſſel is not that which ſinks it to the
tom, but the proper Gravity of the Braſs, ſuperiour to the Specificall
Gravity of the Water: for if the Veſſel were leſs grave than
water, the Ocean would not ſuffice to ſubmerge it. And, give me
leave to repeat it again, as the fundamentall and principall point in
this Caſe, that the Air contained in this Veſſel before the infuſion of
the Water, was that which kept it a-float, ſince that there was made
of it, and of the Braſs, a Compoſition leſs grave than an equall
ty of Water: and the place that the Veſſel occupyeth in the
Water whilſt it floats, is not equall to the Braſs alone, but to the
Braſs and to the Air together, which filleth that part of the Veſſel
that is below the Levell of the water: Moreover, when the Water
is infuſed, the Air is removed, and there is a compoſition made of
Braſs and of water, more grave in ſpecie than the ſimple water, but
not by vertue of the water infuſed, as having greater Specifick
Gravity than the other water, but through the proper Gravity of
the Braſs, and through the alienation of the Air. Now, as he that
ſhould ſay that Braſs, that by its nature goes to the Bottom, being
formed into the Figure of a Ketle, acquireth from that Figure a
vertue of lying in the Water without ſinking, would ſay that which
is falſe; becauſe that Braſs faſhioned into any whatever Figure,
goeth always to the Bottom, provided, that that which is put into the
water be ſimple Braſs; and it is not the Figure of the Veſſel that
makes the Braſs to float, but it is becauſe that that is not purely
Braſs which is put into the water, but an aggregate of Braſs and of
Air: ſo is it neither more nor leſs falſe, that a thin Plate of Braſs
water, doth arrive to the Levell of the univerſall Surface of the ſaid
water. To ſay, in the next place, that water can encreaſe the weight
of things that are demitted into it, is moſt falſe, for water hath no
Gravity in water, ſince it deſcends not: yea, if we would well
der what any immenſe Maſs of water doth put upon a grave Body;
that is placed in it, we ſhall find experimentally, that it, on the
trary, will rather in a great part deminiſh the weight of it, and that
we may be able to lift an huge Stone from the Bottom of the water,
which the water being removed, we are not able to ſtir. Nor let
them tell me by way of reply, that although the ſuperpoſed water
augment not the Gravity of things that are in it, yet it increaſeth the
ponderoſity of thoſe that ſwim, and are part in the water and part
in the Air, as is ſeen, for Example, in a Braſs Ketle, which whilſt it
is empty of water, and repleniſhed only with Air ſhall ſwim, but
pouring of Water therein, it ſhall become ſo grave, that it ſhall ſink
to the Bottom, and that by reaſon of the new weight added thereto.
To this I will return anſwer, as above, that the Gravity of the
Water, contained in the Veſſel is not that which ſinks it to the
tom, but the proper Gravity of the Braſs, ſuperiour to the Specificall
Gravity of the Water: for if the Veſſel were leſs grave than
water, the Ocean would not ſuffice to ſubmerge it. And, give me
leave to repeat it again, as the fundamentall and principall point in
this Caſe, that the Air contained in this Veſſel before the infuſion of
the Water, was that which kept it a-float, ſince that there was made
of it, and of the Braſs, a Compoſition leſs grave than an equall
ty of Water: and the place that the Veſſel occupyeth in the
Water whilſt it floats, is not equall to the Braſs alone, but to the
Braſs and to the Air together, which filleth that part of the Veſſel
that is below the Levell of the water: Moreover, when the Water
is infuſed, the Air is removed, and there is a compoſition made of
Braſs and of water, more grave in ſpecie than the ſimple water, but
not by vertue of the water infuſed, as having greater Specifick
Gravity than the other water, but through the proper Gravity of
the Braſs, and through the alienation of the Air. Now, as he that
ſhould ſay that Braſs, that by its nature goes to the Bottom, being
formed into the Figure of a Ketle, acquireth from that Figure a
vertue of lying in the Water without ſinking, would ſay that which
is falſe; becauſe that Braſs faſhioned into any whatever Figure,
goeth always to the Bottom, provided, that that which is put into the
water be ſimple Braſs; and it is not the Figure of the Veſſel that
makes the Braſs to float, but it is becauſe that that is not purely
Braſs which is put into the water, but an aggregate of Braſs and of
Air: ſo is it neither more nor leſs falſe, that a thin Plate of Braſs