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level one with an opening span ; but if the line was run -along the coast to Awakino Heads the bridge would be a high-level one, crossing the river at the mouth nearly on the line of the tele-graph-wire. The necessary divergence up-river to obtain a low-level bridge would be very awkward and expensive to construct owing to the cliffs on each side of valley. The top of cliff at south side of river at the heads is a little over 90 ft. above high-water mark. The last sailingvessel to enter the river (a scow) had masts reaching a height of 95 ft. above water. An opening span at the heads would not be admissible, as presenting at a critical point an obstruction to the free navigation of the entrance to the port. The alternative line between the Mimi and Tongaporutu Eivers would continue along the coast instead of turning inland up the Mimi Valley. The great obstacles in the way of this piece of line are the White Cliffs, and the crossings of the Mimi, Wai-iti, and Tongaporutu Eivers at right angles to their courses. The White Cliffs rise abruptly from the sea-beach for some 800 ft.; they consist entirely of papa rock. Two tunnels, one 80 chains and one 27 chains in length, would be required, and about 50 chains of the line would be on steep papa-rock sideling. From 52 miles to 57 miles the Awakino Valley becomes very narrow and crooked, with cliffs along the sides and high spurs running out into the bends. The construction-works will therefore be heavy. Several river-crossings and tunnels may be required to keep curvature within the limits. At 57 miles the valley opens out so that the formation - works will be much easier up to 65 miles, where the tunnel is that carries the line into the Waipari Creek Valley. This tunnel will be about 13 chains long. The line follows down the Waipari Creek to the Mokau Eiver, the construction-works being moderate. The line will either descend about 200 ft. to a low-level crossing of the Mokau Eiver, and then grade up the Waikohatu Creek to a saddle leading into the Mckau-iti Valley, or cross the Mokau Eiver by a high-level bridge at the mouth of the Waipari Creek, and proceed up the Mokau and Mokau-iti Valleys. The best route can only be determined by trial survey, as, whichever way the line is taken between Awakino Valley at 65 miles and the Mokau Valley at 76 miles, near Wairere J?alls, the formation-works will, on the whole, be heavy. The latter of the above routes is the best, as avoiding most of the fall to the Mokau Eiver, thus allowing very much better grades. There are two other routes—one vid the north bank of the Mokau Eiver from the Waipari Creek, the other vid the Mangaotaki Valley, the latter being, I am convinced, impracticable, owing to the precipitous nature of the country and the great rise to saddle at Paemako. Between Mokau-iti Eiver at 74 miles and Mokau Eiver at 76 miles there will be a tunnel about 20 chains in length to avoid grading over top of saddle. From 76 miles to Mokau Station, at 94 miles, the end of this route, the line follows up the Mokau Eiver, with occasional divergences to save distance. The formation-works will be easy, except for a mile and a half between 88 miles and 90 miles, where a waterfall in the river occurs, the sudden drop necessitating a short grade to carry line up. From om. Och. (Waitara) to 57 miles, in the Awakino Valley, the height of line above sealevel will vary from 10 ft. to 150 ft.; thence the highest point will be at the junction with central line, which is 690 ft. above sea-level, the greatest rise in any one place on a steep grade being 300 ft., and this may be reduced to half the amount. The only advantage gained by a low-level crossing of the Mokau Eiver at Totoro is to make the line more accessible from the good country to the south. On the whole, I must say that from an engineering point of view this route is an excellent one, and by far the easiest to construct. Estimated Costs. Ngaire Route. Total cost, £865,997 ; length, 103 miles 5 chains. Average cost per mile, £8,403. Waitara Route. Total cost, £1,008,921; length, 95 miles 59 chains. Average cost per mile, £10,538. Awakino Route. Total cost, £751,400; length, 94 miles. Average cost per mile, £7,994. New Zealand Railways opened for Traffic to 31st March, 1898. Total cost, £15,994,000; length, 2,061 miles. Average cost per mile, £7,750. Tables are attached giving the estimated cost with some detail. Country. . Ngaire Route. The country along this route, with the exception of the Tangarakau Gorge and the upper part of the Ohura Valley, is all good pastoral land, besides being suitable for agricultural purposes for the first ten miles from Bltham, and in numerous other smaller areas along the route. Although the Tangarakau Gorge is almost useless immediately adjacent to the line, there are considerable areas of fair country within a short distance. The country as far as 8 miles, near Toko, is situated on the tail of the slope from Mount Egmont. It is fairly flat; the soil is volcanic; thence to about 90 miles, in the Ohura Valley, the country is all clay and papa rock, overlaid by good soil, principally in the form of ridges. Beyond 90 miles the fiat country is covered with pumice, only the hillsides being free, and at 100 miles the papa rock is overlaid with the volcanic rock rhyolite.