IrHl 
A Letter from Mr. TankredRobinfon to Pr- M. L. 
Aug. t3^.i6S'^. concerning the Bridge at St. Efprit 
in France. 
According to yourOrderJmade as manyObfervations 
upon the Fabrick, and defign of the Bridge at Pont 
St. £^m,as my fliort ftay there would permit , 1 fentyou a 
Draught and Defcription, drawn haftily upon the place, 
peradventure you can make nothing of them, unlefs 
affifted by your own Memory. 
This famous l^man Bridge at Potit St. Ejprit is very 
crooked, bowing in many places, and making feveral 
unequal Angles, efpecially in thofe places, where the 
Torrent runsftrongeft,as where theTurret ftandsi^i2.iV.4* 
In which place the Angle is moft unequal, and the great- 
eft ; the Arches are very wide, and have their feet lecu- 
red by two Pedeftals that encompafs them. Both thefe 
Pedeftais have their feveral degrees, or Ranksof jettings 
#ut, like fo many rows of ftairs or fteps, the lowermoft 
order piiftiing oat moft, the others being lefs, and going 
gradually more in j the lecond or uppermoft Pedeftal is 
much lefs than the firft, or lowermoft, being built a lit- 
tle within its lines of circumference, fee N. i, 2. be- 
tween the great Arches there are windows, or fas it werej 
fmall Arches, N\ 3. that come down to the very plane 
of the fecond, or uppermoft Pedeftal, dividing the feet ot 
the great Arches. From this my rude Defcription it apear^ 
to me, that the J{pmans have here contriv'd all polTible 
ways to break gradually the mighty force of the Rhofne, 
and to render its paifage eafy, and inofFenfive to the feet 
of the great Arches; for here we fee fo many feveral 
Palifadoes and Sluces, as may be fufficient to defend this 
wonderful Fabrick againft all ftorms of the Torrent s 
The feveral ranks of ftairs jettino- from the I'edeftals 
