They were really what are known as S curves. Much of the following information is drawn from an 1876 newspaper report (fully transcribed later on this page):-
This bridge is of larger dimensions than any other in connection with the work. It appears it is purely an urban myth. The girders are supported by fifteen cast iron support columns, and these are of circular, not elliptical section. Above we give views representing a portion of the latticed viaduct at Cornbrook, and the bridge which crosses Dawson-street.' 'It is needless to say that the new line between this city and Liverpool has been in use for some time, but the Cheshire Lines Committee's system extends only to Cornbrook from Liverpool, and in order to obtain access to London-road Station it has been and is now necessary to run over a portion of the Manchester South Junction and Altrincham Railway. At the latter place, the outside plate girder is 178 ft.long. There was a fifth phase in the early 1990s, with the coming of Metrolink. The ends of the girders, where they abut upon the central cylinders, will be hid by a cast-iron screw rising to a height of about twenty-four feet above the level of the rails which, like the walls on the abutments, will be turreted.
The 'Three more arches — one of 40 feet span and two of 34 feet — bring us to the Ordsal-lane branch of the South Junction line. 'At Cornbrook there is a bridge with a skew span of 64ft. 'From the canal to the Hulme Locks the line is carried over nineteen arches, one of which, near Hulme Hall-road, has been made wider than the rest, in order to provide, if it should any future tune be thought desirable, a means of communication between Hulme and Salford by a bridge crossing the Irwell near Woden-street. In the 1960s, Stockport Viaduct is 33.8 metres above the bed of the River Mersey, 546.2 metres long and, when built, was 9.4 metres wide.Several contractors were employed in the viaduct's construction including John Tomkinson and Samuel and John Holme.At the peak of the work, around 600 workers were employed in shifts to complete the structure. deep, is wrought iron. The two lines were sufficient for the requirements for a considerable time, but the traffic has during the past six or seven years been so great that it was found absolutely necessary to widen the viaduct. In 1890 the contracts were let, and the big undertaking was commenced. In its course the viaduct runs over the Ship Canal wharves, formerly the property of the Bridgewater Canal Navigation Company —and crosses the Manchester South Junction main line near Deansgate. In 1906 the Cheshire Lines Committee placed a contract with Two arms of the Bridgewater Canal are crossed by this bridge.
Railways could not be bent to tight curves to meet rivers square-on, so bridges often had to be skewed. The lattice girders are 20ft. 'We have come now to the site of the station, which covers about ten acres of land.
6in. All the bridges are fitted with ½ in. An 1849 newspaper report identified nine cast iron arch bridgesThe 1849 report also draws attention to 'an arch over the branch canal at Castlefield which is a great curiosity - indeed it is supposed, by experienced scientific men, that there is not such another arch in this country. The columns are also braced together with diagonal bracings and struts of cast-iron. However, the girder material is steel, which is generally more susceptible to corrosion. Crown-street and Trafford-street are crossed by wrought-iron girder bridges, while Great Bridgewater-street will be spanned by cast-iron arched girders of 48 feet in the clear. Each of the cylinders is formed of cast-iron segments, four in number, in plates six feet in depth, and which are secured together by wrought-iron bolts. The masonry viaducts are fine pieces of work, but it is the cast iron arch bridges which are really worthy of attention, especially when their intricate details have been highlighted by fresh paint. Five people were killed and 27 were seriously injured.