Steel Pipes made at the works of Messrs. Stewarts & Lloyds, Limited, by the Ferguson patent process, although introduced only so recently as 1896, are already in use to a very great extent, and they are specially adapted for use as conduits for water, sewage, gas, or air, and for any working pressure up to 500 lbs. per square inch. They are usually made in 28-ft. lengths and of the following standard internal diameters : - 18, 21, 24, 27, 30, 33, 36, 39, 42, 45, 48, 54, 60, 66, and 72 ins. They are made from acid or basic open hearth steel plates, having an average tensile strength of 27 tons per square inch of plate section.

Compared with cast-iron pipes of equal weight, Ferguson pipes have four and a half times the strength, or, for equal strength, are less than a third of the weight; this effects a considerable saving in first cost, freight, and handling. There is also a saving in cost of making and maintaining of joints, owing to the long lengths in which the pipes are supplied. Again, steel pipes are much more effectively coated than cast-iron pipes by dipping hot in solution, and are thus rendered much less subject to corrosion. Cast-iron pipes have been taken from the ground, after being in use a number of years, through which daylight could not be seen owing to an accumulation of corrosion inside. Steel pipes, on the other hand, when properly coated, have been found as clean inside after twenty years as when first laid.

Cast-iron pipes cannot resist the effects of subsidence, distortion, and shocks to which they are frequently subjected, as pieces are apt to break out of the pipe, leaving it open full bore. This invariably results in heavy loss through waste of water, cost of repairs and relaying, cessation of water supply, and consequential damages. Ferguson pipes, on the other hand, may bend or flatten, but will not break. If by reason of excessive shock or pressure any failure should occur, it is only a crack of limited extent, usually causing little leakage or damage, which can be promptly repaired temporarily.

Compared with riveted pipes of equal strength, Ferguson pipes are little more than half of the weight of single-riveted, and less than two-thirds of the weight of best double-riveted pipes. They remain tight even after long transport by land or sea, whereas riveted pipes invariably leak badly before, and more so after, transport, necessitating constant caulking, with its attendant evils. Moreover, Ferguson pipes, as proved by exhaustive experiments, have 33 per cent. more carrying capacity than riveted pipes, and may consequently be at least 12 1/2 per cent. less in diameter for equal duty.

The examples given below show the differences in cost for a line of Ferguson pipes, cast-iron pipes, and riveted pipes to the following specification : -

The pipe line to be 1 mile long and 45 ins. clear internal diameter, to stand a working pressure of 250 lbs. per square inch, with a factor of safety of four on the average ultimate tensile strength of the pipe material.

First Example. - Cost of a line of Ferguson pipes 45 ins. bore by 3/8 in. thick in 28-ft. lengths with collar joints for lead and having an average ultimate tensile strength of 27 tons per square inch of plate section : -

Second Example. - Cost of a line of cast-iron pipes 45 ins. bore by 1 5/8 in. thick in 12-ft. lengths with spigot and socket joint for lead and having an average ultimate tensile strength of 6 tons per square inch of pipe section: -

Third Example. - Cost of a line of double-riveted steel pipes 51 ins. bore by 5/8 in. thick in 28-ft. lengths with Kimberley collar joints for lead and having an average ultimate tensile strength of 18 tons per square inch of plate section : -

Note. - The riveted pipes are taken as 51 ins. bore to give the same carrying capacity as Ferguson pipes or cast-iron pipes 45 ins. bore.

Copy of Letter received from the Minister for Works, Western Australia

Public Works Department, Perth,

22nd May, 1905. Gentlemen, - In reply to your letter of the 26th ult., regarding the Mephan Ferguson Locking Bar Water Pipes, I have the honour to inform you that the locking bar main of a length of over 350 miles has now been carrying water for about three years without a single failure in any of the locking bar joints, although under a pressure as high as 500 ft. The lead joints joining the several lengths of locking bar pipe to each other occasionally leak and have to be caulked, but this has nothing to do with the class of pipe used, as the same trouble would be experienced with either a welded or riveted pipe. As regards the locking bar joints themselves, practically no trouble has been experienced with these, and, but for the necessity of attending to the lead joints, not more than about three men would be required to patrol the whole line.

I have the honour to be, Gentlemen, Your obedient servant,

(Sgd.) W. D. Johnson,

Minister for Works. Messrs. Stewarts & Lloyds, Limited, Glasgow.