of keeping it fully charged without continuous pumping at the The Author. maximum rate. Having recently returned from the International Railway Congress held at Washington, and subsequent inspection of works under the auspices of the American Railway Association, the Author had nothing but admiration for the directness of American engineering aims; but, on the other hand, it was his opinion that American estimates of cost, especially comparative figures, were not of overmuch value for comparison in other countries, unless full allowance was made for the fact that, so far as he could judge, American home works paid more for materials, etc., than was charged for goods intended for export. Thus Mr. Fuertes stated that the tender for 1-inch steel pipe, 30 inches in diameter, for work at Lynchburg, Virginia, amounted to 168. 5d. per lineal foot in position. It was not quite apparent to the Author whether the cost of valves and specials, culverts. and aqueducts, meters and road-crossings, covering-pipes and contingencies, were or were not included in this figure. Trenchexcavation was not included, and if, for the purposes of comparison, the cost of this item and also carriage by rail from the Western Australian sea-coast inland were deducted from the Coolgardie water-supply figures for identical pipes, the net cost arrived at was 16s. 6d. per foot, inclusive of all the incidental works above mentioned. He considered that this told strongly against the American figures, having in view the fact that the whole of the plates, bars and lead was imported, a very large portion from America itself, and the further fact that wages in that country were 25 to 30 per cent. below those of Western Australia. On the question of the comparative cost of cast iron, raised by Mr. Goument, the Author would direct attention to Mr. John W. Hill's experience at Philadelphia. In the neighbourhood of cheap iron, Mr. Hill found that 60-inch cast-iron pipes, to withstand the low head of 160 feet, cost £4,650 per mile more than steel pipes would have been obtained for. Apart from this, neither cast-iron nor ferro-concrete was in the Author's opinion suitable for the high pressures of the Coolgardie watersupply. These could no doubt have been reduced by introducing more pumping-stations, but unprofitably, owing to the enhanced cost of pumping. The actual life of steel pipes, raised by Messrs. Goument and List, was another question, but it did not enter too largely into the pipes dealt with in the Paper, for, as therein stated, a sinking-fund of 3 per cent. per annum on the whole cost of the works has been provided by Act of Parliament to discharge the loan at a comparatively early date. The Author was glad to note

The Author. Mr. Herbert's good opinion of the locking-bar pipe, but considered that he had rated its virtues somewhat too highly. For the Coolgardie water-supply, at any rate, the price asked, length for length and thickness for thickness, was higher for lockingbar than for riveted pipe. He did not propose to follow Mr. Herbert in his calculations as to the comparative cost and economy of pipes of various diameters, as they appeared to be based on the fallacy that a 31-inch diameter pipe laid complete cost of the cost of a main 32 inches in diameter. This, at any rate, was not the Author's experience. Professor Campbell Brown's statement that asphalt was not suited for use in a composition employed for pipecoating was too sweeping. The lime contained in the asphalt would no doubt be injuriously affected by some waters, but in numerous cases this material had served excellently, instances being forthcoming in the works mentioned by Messrs. Fuertes and Moncrieff. The coating referred to by Mr. Smith must have been wrongly made or applied, or used in some unsuitable position, to have perished, while exactly similar coating had served well in South Australia, as mentioned by Mr. Moncrieff. The precautions against corrosion suggested by Mr. List would surely prove altogether too expensive for general use, even if they were successful, which was not certain. With reference to the jointing of the pipes, no yarn had been used, the lead being kept from running into the pipe by temporary expansive rings; as the sleeve-rings varied slightly in diameter the caulking-tools used also varied in size; the caulking-machine was in the Author's opinion eminently suited for use on ordinary socketed pipes; and there was no doubt that a machine suitable for caulking at the locking-bar could be devised and would save money. The cost of caulking in South Australia mentioned by Mr. Moncrieff did not appear to have been lower than on the Coolgardie watersupply when due allowance was made for the larger pipe and for higher wages. On the latter work the cost of hand-caulking was 4s. 3d. on a 30-inch pipe, equivalent to 38. 8d. on the 26-inch pipe used in South Australia. The Coolgardie wages were, per day of 8 hours-Foreman, 16s. 6d.; hand-caulkers, blacksmith, leadmelter, etc., 128. 6d. ; labourers, 108.; and the corresponding rates in South Australia were, according to the Author's notes, 10s. 6d., 78. 6d., and 68. 6d.-less than two-thirds on the average. Reducing the Coolgardie figures for 26-inch pipe even to two-thirds, the cost per joint was less than 2s. 6d., the lower of the South Australian figures; and as mentioned in the Paper, machine-caulking cost 18. less per joint, besides saving in depth of manhole and ensuring uniform

work. In reply to the concluding portion of Mr. John W. Hill's The Author. remarks, the Author had obtained in India all but absolute watertightness in a new cast-iron main 12 inches in diameter and about 2 miles long. It was more than questionable, however, whether it was worth striving after such a condition of things. But even in the rapid work of the Coolgardie water-supply there were lengths from which the leakage was less than the figures given on p. 74. Thus the 36 miles of main west of station No. 4, gauged statically for 2 days, after being filled for the first time, showed a loss of 119 gallons per mile per diem, and after attention to visible leakage it showed a month later 31 gallons per mile per diem, and another month later 35 gallons per mile per diem, or, say, 13 pint per joint. The Author concurred with Messrs. Bruce and Hill as to the value of asphalt lining for reservoirs, and he had used it on the Western Australian goldfields for this purpose; but he employed 1 inch of asphaltic mortar without concrete or puddle, and found it sufficient for a head of 15 to 20 feet of water, while the cost of construction was one-fourth to one-third of that of a sufficient thickness of concrete lining. It was not possible to concur in Mr. Marsh's remarks as to the inutility of the wires buried in the concrete lining of the Bulla-Bulling reservoir. This work had been carried out in the height of a hot summer and the lining must have been subjected to great tensile stress when cooled by the admission of water. One after another of several concrete reservoirs on the goldfields had suffered from cracks all over, and consequent leakage, whereas the Bulla-Bulling lining had opened only at the expansion-joints, as already stated. There was no doubt, as Mr. Fairley said, that the capital cost of the pumping-machinery would have been reduced by employing three sets at each of the last four stations, but this would have meant two sets working at one time instead of one as in the adopted scheme; and at West Australian rates of wages this would have meant an appreciable increase in the cost of maintenance. Other advantages would also have been lost. Mr. Phipps Williams's calculations on the possible saving in pumping-machinery, if intended to be taken literally, were, the Author regretted to say, beyond him. Was it intended to imply that small pumps cost the same amount per horse-power to instal as large ones, and that working small pumps three shifts cost no more than doing the same amount of work in one shift with large pumps? How also would the increasing demand (increasing until the ultimate estimated amount should be reached) have been provided for with such small pumps as Mr. Williams considered enough? The small pumps, unless of varying

The Author. power, could not have been placed at the stations decided on as best for the ultimate supply, and nothing but peripatetic pumpingstations would have permitted of uniformity and economy in size of pumps without excessive pressure on the main as the horse-power rose in keeping with the demand. The details of cost of sundry works referred to by Mr. Moncrieff had not been given by the Author, as he was in hopes that they would be supplied to the Institution. later on by his principal assistant, Mr. Reynoldson, to whom the Author, being now engaged in London and unable therefore to give effect to Mr. Crowell's suggestion of further tests of friction, etc., from time to time, looked for compliance in this direction also. In conclusion he desired to express his obligations to those who had commented so kindly on the work carried out. Very few indeed, besides engineers, credited the intense anxiety entailed during construction of a work of this kind; and none but engineers appreciated the difference between the reasons for success and failure in connection with Colonial works.

4 April, 1905.

Sir ALEXANDER R. BINNIE, Vice-President,
in the Chair.

It was announced that the Associate Members hereunder mentioned had been transferred to the class of

Members.

And that the following candidates had been admitted as

Students.