Note 1 — INTRODUCTORY CHAPTER. AQUEDUCTS, FOUNTAINS, ETC.
Reading edition
It is proper to remark that, the pier at each extremity, of the range of arches of eighty feet span, has an extra thickness, making it a pier of equilibrium; this is also the case with the one in the centre of that range of arches, so that on each shore and in the centre of the river this additional security has been given.