the&longs;e other two in a ju&longs;t Relation or proporti­<lb/> onate Interval, which Interval is the equal re­<lb/> lative Di&longs;tance which this Number &longs;tands from <lb/> the other two. </s>
<s>Of the three Methods mo&longs;t <lb/> approved by the Philo&longs;ophers for finding this <lb/> Mean, that which is called the arithmetical is <lb/> the mo&longs;t ea&longs;y, and is as follows. </s>
<s>Taking the <lb/> two extreme Numbers, as for In&longs;tance, eight <lb/> for the greate&longs;t, and four for the lea&longs;t, you add <lb/> them together, which produce twelve, which <lb/> twelve being divided in two equal Parts, gives <lb/> us &longs;ix.<lb/> <arrow.to.target n="table16"/></s></p>
<table><table.target id="table16"/><row><cell>8</cell><cell/><cell>4</cell></row><row><cell/><cell>12</cell><cell/></row><row><cell/><cell>6</cell><cell/></row></table><p type="main">
<s>THIS Number &longs;ix the Arithmeticians &longs;ay, is <lb/> the Mean, which &longs;tanding between four and <lb/> eight, is at an equal Di&longs;tance from each of <lb/> them.<lb/> <arrow.to.target n="table17"/></s></p>
<table><table.target id="table17"/><row><cell>8.</cell><cell>6.</cell><cell>4.</cell></row></table><p type="main">
<s>THE next Mean is that which is called the <lb/> Geometrical, and is taken thus. </s>
<s>Let the &longs;mall­<lb/> e&longs;t Number, for Example, four, be multiplied <lb/> by the greate&longs;t, which we &longs;hall &longs;uppo&longs;e to be <lb/> nine; the Multiplication will produce 36: <lb/> The Root of which Sum as it is called, or the <lb/> Number of its Side being multiplied by it&longs;elf <lb/> mu&longs;t al&longs;o produce 36. The Root therefore <lb/> will be &longs;ix, which multiplied by it&longs;elf is 36, <lb/> and this Number &longs;ix, is the Mean.<lb/> <arrow.to.target n="table18"/></s></p>
<table><table.target id="table18"/><row><cell>4 Times 9</cell><cell>36</cell></row><row><cell>6 Times 6</cell><cell>36</cell></row></table><p type="main">
<s>THIS geometrical Mean is very difficult to <lb/> find by Numbers, but it is very clear by Lines; <lb/> but of tho&longs;e it is not my Bu&longs;ine&longs;s to &longs;peak <lb/> here. </s>
<s>The third Mean, which is called the <lb/> Mu&longs;ical, is &longs;omewhat more difficult to work <lb/> than the Arithmetical; but, however, may be <lb/> very well performed by Numbers. </s>
<s>In this the <lb/> Proportion between the lea&longs;t Term and the <lb/> greate&longs;t, mu&longs;t be the &longs;ame as the Di&longs;tance be­<lb/> tween the lea&longs;t and the Mean, and between the <lb/> Mean and the greate&longs;t, as in the following Ex­<lb/> ample. </s>
<s>Of the two given Numbers, let the <lb/> lea&longs;t be thirty, and the greate&longs;t &longs;ixty, which is <lb/> ju&longs;t the Double of the other. </s>
<s>I take &longs;uch <lb/> Numbers as cannot be le&longs;s to be double, and <lb/> the&longs;e are one, for the lea&longs;t, and two, for the <lb/> greate&longs;t, which added together make three. </s>
<s>I <lb/> then divide the whole Interval which was be­<lb/> tween the greate&longs;t Number, which was &longs;ixty, <lb/> and the lea&longs;t, which was thirty, into three <lb/> Parts, each of which Parts therefore will be <lb/> ten, and one of the&longs;e three Parts I add to the <lb/> lea&longs;t Number, which will make it forty; and <lb/> this will be the mu&longs;ical Mean de&longs;ired.<lb/> <arrow.to.target n="table19"/></s></p>
<table><table.target id="table19"/><row><cell>30</cell><cell/><cell>60</cell></row><row><cell>1</cell><cell/><cell>2</cell></row><row><cell/><cell>3</cell><cell/></row><row><cell>3</cell><cell/><cell>30</cell></row><row><cell/><cell/><cell>10</cell></row><row><cell/><cell>30</cell><cell/></row><row><cell/><cell>10</cell><cell/></row><row><cell>30</cell><cell>40</cell><cell>60</cell></row></table><p type="main">
<s>AND this mean Number forty will be di&longs;­<lb/> tant from the greate&longs;t Number ju&longs;t double the <lb/> Interval which the Number of the Mean is <lb/> di&longs;tant from the lea&longs;t Number; and the Con­<lb/> dition was, that the greate&longs;t Number &longs;hould <lb/> bear that Portion to the lea&longs;t. </s>
<s>By the Help of <lb/> the&longs;e Mediocrites the Architects have di&longs;cover­<lb/> ed many excellent Things, as well with Rela­<lb/> tion to the whole Structure, as to its &longs;everal <lb/> Parts; which we have not Time here to par­<lb/> ticularize. </s>
<s>But the mo&longs;t common U&longs;e they <lb/> have made of the&longs;e Mediocrities, has been how­<lb/> ever for their Elevations.</s></p>
<p type="head">
<s>CHAP. VII.</s></p>
<p type="head">
<s><emph type="italics"/>Of the Invention of Columns, their Dimen&longs;ions and Collocation.<emph.end type="italics"/></s></p>
<p type="main">
<s>It will not be unplea&longs;ant to con&longs;ider &longs;ome <lb/> further Particulars relating to the three <lb/> Sorts of Columns which the Ancients invent­<lb/> ed, in three different Points of Time: And it <lb/> is not at all improbable, that they borrowed the <lb/> Proportions of their Columns from that of the <lb/> Members of the human Body. </s>
<s>Thus they <lb/> found that from one Side of a Man to the <lb/> other was a &longs;ixth Part of his Height, and that <lb/> from the Navel to the Reins was a tenth. </s>
<s>From <lb/> this Ob&longs;ervation the Interpreters of our &longs;acred <lb/> Books, are of Opinion, that <emph type="italics"/>Noah<emph.end type="italics"/>'s Ark for <lb/> the Flood was built according to the Propor­<lb/> tions of the human Body. </s>
<s>By the &longs;ame Pro­<lb/> portions we may rea&longs;onably conjecture, that the <lb/> Ancients erected their Columns, making the <lb/> Height in &longs;ome &longs;ix Times, and in others ten <lb/> Times, the Diameter of the Bottom of the