( 68i ;

$. The Age of Trees is to be known by the Number os RJngs to be ftenwhen the Trce is cut a-thwart, in each of which Rings is one Circle uf largeOpen Pipes ; now the sewer of these Large Pipes , the Stronger the Timbcr is:wherefore by Confequence thole Trees that malte the Largest Growth in aYear, must be the Cloler and Stronger, and therefore thole Trees that Growin P! 'arm Countrics Grow fastest, and are the Best and Toughest Timbcr', whichhe conhrnu by Riga and Dant^ick. Crns which is ot Slow Growth, and provesSpongyand Brittle Timbcr , whereas the Contrary is Oblervable in EngUfhzndFrench Ocl which grows Laster, and is Excellent Timbcr.

V. i. This Famous Renum Bridge at Pcnt St. Esprit is very Crooked,^ 1 ’^'^ 4fBowing in many places, and making leveral unequal Angles, especially in F r ' 3 nce •, by'vr.thole Places, where the horrent runs strongtst, as where the Tuirct stands. Tankred4. In which Place the Angle is moli Uncquai, and the greatest ; the Arches 5

are very VVide, and have their Feet lecured by two Pcdestals that encompals F ^°them. Both thele Pcdestals have their leveral Degrees or Ranks of Jettings out,like Ib many Rows of Stnirs or Steps, the Lowermost Order pulhing outmust, the others bcing Leis, and going gradually more in ; the Sefcondor Uppermost Pedestal is much leis Man the First or Lowermost, being Builta little within its Lines of Circumfcrence; 1, Between the Great Archestlure are IVindcvs, or ( as it were ) (mali Arches ; z. that come down tothevery Plane ot the Second, or Uppermost Pedesal dividing the Feet of thegreat Arches. Front this my Rude Delcription it appears to nie, that theRomans have here contrived ali poiLblc ways to break gradually the ntightyForce of the Rjxfic, and to rentier its passage eafie, and inoffenfive to theFeet cf the great Arches ; fer here we ite (b many leveral Palisadoes and Siu-ces, as may be Itiflicient todefend this wor.derful Fabrick against all Storms ofthe Torrent; the leveral Ranks cf Stairs jctting from the Pcdestals ( for thentost part Triangulari)’ built, and Faced well with Free-stone ) opposing andbreaking the Stream leverally, I mean, not altogether or at the farne time, byrealbn ot their various Inequalities in Standing Out: in cale the Flood Ihouldfwell so high ( as it frequcntly does ) as to cover both the Pedestals , then theimuli Arches , Dividing the Feet of the great ones, help to convey the Wa-ter through, which otherwile might endanger the great Aichcs.

%. That which leems the Fcot of the Arch is an Horizontal Arch gradually By Dr. Li-stercontractcd, every Stone being cf vast Lcngth and Wedge like, laid Level' 6 - f- 5 S 5-with the Water. This I Ipeak by Memory.

?- I he Stately Modem Bridge at Avigncn bath yiclded in many Places Cc m t*rcd withto the extream .Rapidity, and violence of the Rjjc/ne. Its fall in my opinion b

may be Alcribed to three defects. First, it was not so Multangular, as that zrr.Tank. Ro-at St. Esprit : Secondly, it wanted in three or four places, the little Arches binson.Dividing the Feet of the Great ones, and in thole paris it bath lufttred mostfor where thole uleful Sluces are, there I oblerved the Bridge to stand ,still themostintire. Thirdly, the Pedestals (orasyou very properly call them HorizontalArches) were not io Geometrically and exactly Laid, as thole of Ppnt St. Esprit,rtieir Jcttiugs out were few, and they not gradually contracte« ; 1 b that theForce of the Stream must be the greater upon the Fabrkk.

Vol. I. ' s r 1 ' s

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