604 PROCEEDINGS OF SECTION J. 



Parramatta Junction to Penrith, twenty-one mileS, is thirty 

 chains. Between Penrith and Bathurst, a distance of one hundred 

 and eleven miles, the smallest radius of a curve is five hundred 

 and twenty-eight feet, the total length of such curves being five 

 miles, including those upon the two zig-zags. There are also on 

 this length twenty miles of curves, ranging from eight to twelve 

 chains radius. Between Bathurst and Orange the smallest radius 

 of a curve is twelve chains. From Orange to Bourke the smallest 

 radius of a curve is twenty chains. On the line from Newcastle 

 to Murrurundi, with the exception of one curve of twenty chains 

 radius through the town of Muswellbrook, there is no curve of a 

 smaller radius than thirty chains. From Murrurundi to Tam- 

 wortli the smallest radius of a curve is twelve chains on ascending 

 and descending the Liverpool Range. From Tamworth to Tenter- 

 field the sharpest curve occurs three hundred and fifty-seven miles 

 from Newcastle. It is 27.14 chains long and ten chains radius. 

 There are 89.95 chains in four lengths of twelve chains radius, 

 and 63.20 chains in two lengths of eleven chains radius. On the 

 line from Strathfield to Waratah there are four curves of eleven 

 chains radius of a total length of 62.50 chains, and two curves 

 of twelve chains radius of a total-length of 33.65 chains. From 

 Wallerawang to Mudgee the two sharpest curves are twelve chains 

 radius of a total length of 65.79 chains. There are also curves 

 of fourteen, fifteen, sixteen, seventeen, and twenty chains radius. 

 On the Illawarra line the three sharpest curves are ten chains 

 radius of a total length 53.37 chains. The remaining sharp 

 curves on this line are eleven, twelve, and fourteen chains radius. 



WORKS. 



From Sydney to Parramatta the first work of importance is 

 the Redfern tunnel, under the intersection of Cleveland and 

 Regent streets. It was originally built of stone and brick for a 

 double line of way, but it has recently been reconstructed for four 

 lines of way, with plate-web girders and buckled plates. There 

 are several minor bridges formed with plate-web girders varying 

 in span from thirty feet to fifty feet, and there are foot-bridges or 

 subways at the various suburban stations. The most important 

 structure occurs between Petersham and Summer Hill stations, 

 where a stone viaduct of nine spans has been replaced by an iron 

 bridge of three spans of ninety feet, each consisting of four main 

 girders, somewhat resembling a Pratt truss in design, with eye- 

 bars and pin connections where the members are in tension. The 

 main girders are spaced about eight feet centre to centre, and are 

 braced together in a vertical plane with diagonal bracing ; 

 the height of the viaduct in the deepest place is sixty feet. The 

 deck of this bridge is constructed on the American principle, 

 which consists of cross-sleeper timber beai^ers fixed on the top of 

 main girders. They are ten by ten in section, and are spaced 



