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the naked flooring of the roadway is in my opinion unnecessarily loaded with timber; it is composed of transverse girders, longitudinal binders and transverse joists; now I think that the binders may be dispensed with, the girders being placed somewhat closer together to diminish the bearing of the joists, and diminished from the centre towards each end, similarly to the transverse joists (which would become longitudinal) to give a "hogging" to the roadway. The other point is that to make security doubly sure and to compensate any defects in the timber, I should be inclined to give the strutting towards the centre of the bridge, where they are of considerable length, a trifling increase in scantling, say to 7 inches square, instead of 7"x5". The duty of this strutting is lighter than that in a truss, the object being merely to stiffen and to restrict the undulatory motion of a suspension bridge for which they are sufficient, but if only for proportion sake, for the longer the strut the more with the same weight it is inclined to buckle, the increase should be given to the longer struts. I am not quite satisfied that there would not be an excess upon the designer's estimate which is not in sufficient detail to enable me to go critically into it, as neither quantities nor rates are given. I observe however that in the preliminary description and remarks he states in a note the rates respectively for puriri and rimu; these rates, as far as I can judge, not being aware of the ruling prices of the locality, are fair, and if the timber is carried out at those rates with a competent addition for labor, that item will probably be sufficient. Of the item for masonry I am doubtful, especially considering that it is for a great part an hydraulic work, in executing which unforeseen difficulties may occur involving considerable outlay; and the items for wrought and cast iron appear small. Further I do not observe any sum voted for scaffolding, for this, however, an allowance may have been made under the several items. These doubts, I think, should not affect the award of a premium, especially if the designer has fairly and candidly given a second estimate exceeding the amount proposed for a timber bridge, providing for timber material of a superior and more durable nature than that which he could afford to use if the amount to be expended was limited to the sum of £1500 or thereabouts. Finally, in respect to this design, I would wish to recommend that if its principle should be carried into execution, its designer should be asked to consider whether he would not so far modify it as to make but one span of the bridge, which might I think without injudiciously encroaching on the water way of the river be limited to say 135 feet, 15 feet only more than his large span at present, the encroachment being made on the East bank where the depth and consequently the rapidity of the stream at the part where the encroachment would be made would be very small and that only at the highest freshets.

Nos. 13 and 14 by the same hand, which only differ in the abutments, I shall consider as one design. The trussed bridge itself is unobjectionable, nay good, perfectly practicable, simple and inexpensive in construction, and easily susceptible of repair in its component parts; yet I am bound to take the design as a whole into consideration, and doing so I must strongly object to the project of making the proposed embankments. They would narrow the waterway, in one of the designs, No. 13, V Z, according to the designer himself to the extent of one-sixth, and I have little doubt they would be washed away, especially that on the East bank, and thus the ground plates of the abutments would be laid bare and the whole abutments be exposed to the violent concussions of floating trees, jeopardising the whole structure. Further there is an absence of horizontal strutting towards 5 feet, which is too great. It is to be regretted that the designer, who has evidently taken pains with his subject and considered almost every necessary point, including the facilities (scaffolding) for raising his structure, should have fallen into the error above adverted to which renders his design ineligible; had it not existed, and secure abutments had been proposed, I should have recommended the design (the two considered as one) from the very suitable construction of the main trusses as deserving the second premium. I will also remark that the Estimate is the most fairly drawn of the whole.

No. 15 is an imitation of the American lattice bridges which possess advantages in point of simplicity and facility of construction and repair, and the principle might be advantageously adopted for a bridge in the locality. The designer, however, in his desire doubtless to diminish his Estimate has cut his trusses too fine both in scantling and depth. In practice the scantling of these lattice bridges, is according to the span, from 10" by 3" to 12" by 3½", with double trusses on each side of the bridge substantially connected together through the string pieces, and the depth of the trusses as a rule is one-twelfth to one-tenth of the span. Now the lattice bars of this design are 6"x 4" the latter dimension