LXXXVIII. DISCUSSION. 
Mr. C. W. Dartey, Engineer-in-Chief for Public Works, 
remarked that it was highly gratifying to find that the levels 
taken by the Department of Harbours and Rivers along the river 
Murray more than twenty years ago, had proved to be so accurate, 
and had afforded so useful a means of checking the water con- 
servation levels taken in recent years. It spoke well too for the 
manner in which the work was conducted, that many of the bench 
marks were still available and in a good state of preservation. 
He was under the impression that a great part of the work was 
done by very junior officers of the department. 
Mr. McKinney in replying to remarks which were made said 
that Mr. Halligan’s contribution to the discussion was more 
supplementary than critical, and he quite concurred in the opinion 
he expressed, that the tabular statement which he prepared from 
the information in his paper placed in a clearer light the results 
of the closes of the circuits referred to. In regard to the omission 
to mention the nature of the country through which the lines 
were levelled, he assumed, as Mr. Halligan suggests, that those 
present had a fair general knowledge of this point. As the 
question had been raised, he might state that asa general rule the 
lines were through plain country, the outline being varied at long 
intervals by creeks and sand ridges. Bench marks were fixed at 
every half mile, and occasionally at important points in addition. 
With regard to Mr. Haycroft’s remarks, there was one point in 
_ which he appeared to have misunderstood the author. This referred 
to mistakes made in Western America. The abstract of Mr. 
Haycroft’s remarks conveyed the impression that surveys for 
American irrigation works had been described as inaccurate. If 
Mr. Haycroft would refer to the paper, he would firid that what 
was stated was that in the early days of irrigation enterprise in 
the Western States, surveys were in some cases dispensed with 
altogether, and were in other cases very incomplete, and that 
Serious losses had arisen from these causes. He was well aware 
of the remarkable development of irrigation in the Western States 
_and of the conditions — enminted it, but there was abundant — 
