The abſolute

Gravity of So

lids, are in a pro

portion com

pounded of their

Specifick Gravi

ties, and of their

Maſſes.

Gravity of So

lids, are in a pro

portion com

pounded of their

Specifick Gravi

ties, and of their

Maſſes.

Let A and B be two Solids. I ſay, that the Abſolute Gravity

of A, hath to the Abſolute Gravity of B, a proportion com

pounded of the proportions of the ſpecificall Gravity of A, to

the Specificall Gravity of B, and of the Maſs

A to the Maſs B. Let the Line D have the

[Figure 4]

ſame proportion to E, that the ſpecifick

Gravity of A, hath to the ſpecifick Gravity

of B; and let E be to F, as the Maſs A to the

Maſs B: It is manifeſt, that the proportion

of D to F, is compounded of the proportions

D and E; and E and F. It is requiſite,

therefore, to demonſtrate, that as D is to F, ſo the abſolute Gravity

of A, is to the abſolute Gravity of B. Take the Solid C, equall in

Maſs to the Solid A, and of the ſame Gravity in ſpecie with the Solid

B. Becauſe, therefore, A and C are equall in Maſs, the abſolute

Gravity of A, ſhall have to the abſolute Gravity of C, the ſame pro

portion, as the ſpecificall Gravity of A, hath to the ſpecificall Gravity

of C, or of B, which is the ſame in ſpecie; that is, as D is to E. And, be

cauſe, C and B are of the ſame Gravity in ſpecie, it ſhall be, that as

the abſolute weight of C, is to the abſolute weight of B, ſo the Maſs

C, or the Maſs A, is to the Maſs B; that is, as the Line E to the Line

F. As therefore, the abſolute Gravity of A, is to the abſolute

Gravity of C, ſo is the Line D to the Line E: and, as the abſolute

Gravity of C, is to the abſolute Gravity of B, ſo is the Line E to the

Line F: Therefore, by Equality of proportion, the abſolute Gra

vity of A, is to the abſolute Gravity of B, as the Line D to the

Line F: which was to be demonſtrated. I proceed now to demon

ſtrate, how that,

of A, hath to the Abſolute Gravity of B, a proportion com

pounded of the proportions of the ſpecificall Gravity of A, to

the Specificall Gravity of B, and of the Maſs

A to the Maſs B. Let the Line D have the

[Figure 4]

ſame proportion to E, that the ſpecifick

Gravity of A, hath to the ſpecifick Gravity

of B; and let E be to F, as the Maſs A to the

Maſs B: It is manifeſt, that the proportion

of D to F, is compounded of the proportions

D and E; and E and F. It is requiſite,

therefore, to demonſtrate, that as D is to F, ſo the abſolute Gravity

of A, is to the abſolute Gravity of B. Take the Solid C, equall in

Maſs to the Solid A, and of the ſame Gravity in ſpecie with the Solid

B. Becauſe, therefore, A and C are equall in Maſs, the abſolute

Gravity of A, ſhall have to the abſolute Gravity of C, the ſame pro

portion, as the ſpecificall Gravity of A, hath to the ſpecificall Gravity

of C, or of B, which is the ſame in ſpecie; that is, as D is to E. And, be

cauſe, C and B are of the ſame Gravity in ſpecie, it ſhall be, that as

the abſolute weight of C, is to the abſolute weight of B, ſo the Maſs

C, or the Maſs A, is to the Maſs B; that is, as the Line E to the Line

F. As therefore, the abſolute Gravity of A, is to the abſolute

Gravity of C, ſo is the Line D to the Line E: and, as the abſolute

Gravity of C, is to the abſolute Gravity of B, ſo is the Line E to the

Line F: Therefore, by Equality of proportion, the abſolute Gra

vity of A, is to the abſolute Gravity of B, as the Line D to the

Line F: which was to be demonſtrated. I proceed now to demon

ſtrate, how that,