Note 110 — Chapter VII · RAILWAY BRIDGES AND VIADUCTS.
Reading edition
Though it is convenient to explain the nature of the strains in the Saltash bridge as an arch and suspension bridge combined, it is not intended to imply that there is any virtual difference between this truss and the one at Chepstow, for in both the strain on the tube counteracts the strain on the chains, though the one tube is curved and the other straight.