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the worm: it consists of driving thickly round the piles from the surface to the ground, iron copper nails; this completely prevents the worm from adhering to the timber and is not expensive.

I have, &c.

JAMES FAWTHROP,
Harbor Master.

Charles Brown, Esq.,
Superintendent, New Plymouth.

122, Flinders Lane, East Melbourne,
April 18th, 1862.

Sirs,—I received your letter in due course and am sorry that I was not able earlier to give it my attention. I have much pleasure now in furnishing the particulars you ask for the New Zealand Government in reference to the construction of the Jetty at Portland Bay.

I presume that the arrangement of Roadway in connection with the land end of Jetty, and also the construction of goods shed are dependent altogether upon local features and therefore pass them to give a description of the Jetty.

It is eight hundred feet long, sixteen feet wide, and ten feet high above low water; the tide rising about two feet, and the depth of water at the end is about sixteen feet.

It is constructed on transverse rows of piles ten feet apart, each row containing four piles equal distances apart. The piles are twelve inches diameter at the small or bottom end and are shod with iron shoes and driven with a cast-iron ram weighing fifteen hundred weight.

Each row is then secured with a cap, twelve inches square morticed and tenoned on to top of piles, said cap being sixteen feet long and finishing fair at each end with sides of jetty. Longitudinal beams twelve inches square (four in number) are then fixed on caps, one standing directly over each pile, these are continued in the same line the entire length of jetty, the end joints being made on the bearings on cap.

The decking or flooring is six inches wide four inches thick and sixteen feet long, laid transversely and secured to the longitudinal beams by trenails one inch diameter.

Two lines of tramway leave a space for foot passengers in the middle of the jetty and a kerb and hand-rail is fixed on each side of the jetty.

The foregoing particulars require supplementing by a description of the method of strengthening the jetty by wales and braces to counteract the lateral and cross action of the sea, it is as follows:—

A continuous longitudinal wale twelve inches by six inches is bolted to the piles on each side the jetty at low water mark, these with the two outside longitudinal beams receive the notched ends of diagonal braces (twelve inches by six inches) one of which being bolted to each side of each row of piles completes the construction of main Jetty.

That portion of the outer end of Jetty used for vessels lying alongside is protected by being injured by the surging of vessels by a row of fender piles driven ten feet apart forming a continuous row eighteen inches from each side the Jetty.

A cap twelve inches square is fixed on top of these piles and a wale twelve inches by six inches is bolted also to these piles at low water level.

Transverse tie beams ten feet apart pass under main Jetty rest upon and are secured to caps, and with a pair of transverse diagonal braces are fixed to each pair of fender piles—the notched ends of each brace abutting respectively on wale and cap and the sides of same being bolted to piles.

These piles are driven at distances intermediate between rows forming main Jetty, and are so much lower than main Jetty as to allow tie beams &c. being fixed under it.

I have now described every portion of the construction in detail, any general remarks regarding the suitability, strength, &c., would perhaps be better described by yourselves.

I would only add that were the New Zealand Government carrying out any similar works, I should be glad to tender for them, sufficient time being given for that purpose.

I remain, &c.,
CHARLES BAILLIE.

To Messrs. Henry Learmouth & Co., Portland.