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covered by all the circles to the fpace occupied by all 
the interftices, when each circle is infinitely dimi- 
nilhed, and the number of them fo infinitely in- 
crealedj that the /pace over which they fpread is ot a 
finite magnitude, is that of | the area of one circle 
to the whole area of one interftice. And the area 
of any one interftice is equal to the difference of the 
area of the equilateral triangle, formed by the right 
lines joining three adjacent centers, and i the area of 
one of the circles* 
Problem II. 
To determine the greateft pofible denfity of an in- 
fnitely thin cruji compojed of equal JpheruleSy having 
their centers all in the fame plane. 
i 
From the number 39 fubtrad its. third part. To 
the number 4 add the third part of 39. The re- 
mainder is to the fum, that is,, 26 is to 17, very 
nearly, as the fpace occupied by all the matter to 
the fpace occupied by all the pore, in an infinitely 
thin cruft, of the greateft poffible denfity, compofed 
of equal fpherules, having all their centers in the 
fame plane. 
Demonstration. 
Upon a bafe of innumerable infinitely fmall circles, 
arranged in the dofeft manner poftible, (according to 
Prob. I.) imagine right cylinders to be ereded, each 
cylinder having one of the little circles for its bafe, 
and its altitude equal to the diameter of its bafe! 
Thefc 
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