CIV. DISCUSSION. 
If the author’s statement was correct he thoughi. that the coin- 
cidence was remarkable, and he also noticed that Mr. Williamson, 
M. Am. Soc. C.E., had used an identical device in a design which he 
submitted for the Newtown Creek Bridge, Brooklyn, N.Y. 
Mr. Haycroft would wish to add, that the author was to be 
congratulated on the type of side spans referred to by him as the 
1893 standard type, and there could be no doubt as to the vast 
superiority of this type when compared with the one it supplanted, 
which was in existence when Mr. McDonald was Engineer for 
Bridges, the principal improvements being the abolition of the 
unnecessary diagonal members in the panels, the removal of 
secondary stress in the bottom boom, and the facility with which 
decayable parts could be removed with a minimum of interruption 
to traffic. : 
Mr. GrimsHaw said he found, on reference to the paper, that 
the timber used in this bridge was obtained in New South Wales 
and carried a very considerable distance. This struck him be 
rather remarkable, seeing that abundance of red gum was obtain- 
able near the site of the bridge. No doubt the particular timber 
used was specified for and this would account for it, but he 
thought red gum could be obtained in the neighbourhood of Swan 
Hill at 2/6 or 3/-. He noticed also that the ironwork was con- 
structed in Melbourne, and it might be explained how Melbourne 
firms secured it against English competitors and if tenders were 
invited in the old country. 
__In regard to the design it was of course very evident that this 
was just the place for a bridge of this description, there being 2° 
high masted vessels to go under it. As regards the reduced cet 
of the Swan Hill bridge as compared with that constructed at 
Tocumwal, this was no doubt to be accounted for in the shallower 
foundations and the fact that the plant. used for the latter wee 
available for the former. With regard to the reference made to 
the similarity of design in the bridge under discussion and ee: . 
Chicago bridge, it was of course quite possible that two engineers - “ 
should hit upon similar designs at the same time. 
