205 



the pontoons themselves affected by currents and winds, must involve a certain 

 amount of swinging motion, horizontally or laterally ; besides the tops of the 

 rods were not all vertically over the hooks in the port-holes. 



To allow for this the upper washer of wrought-iron was rounded in the 

 bottom, and rested and fitted in a hollow recess in the cast-iron washer or 

 plate, which hollow was turned so as to fit accurately to the bottom of the 

 upper washer. This then allowed to the upper washer, the screw, the nut, 

 and top of rod, a certain amount of oscillation, to suit which the aperture in 

 the cast-iron washer, or plate, was beveled out somewhat towards the lower 

 edge. (See sketch). 



A set of counter-balance weights had also to be provided to carry the 

 weight of the rods, when adjusting or fleeting the screws. These weights were 

 carried by ropes attached to the upper part of the rods, and passing over 

 sheaves placed in the cross logs which rested on the pontoons. The weight 

 was made sufficient to balance the weight of rod, and this arrangement allowed 

 the pontoons to rise and fall with the tide. 



The four pontoons were placed two on each side of the sunken vessel, so 

 that a space was left between them over the wreck, about one foot more 

 than the breadth of the "Taranaki." 



Twenty-two sets of cross beams, each carrying two lifting rods, rested on the 

 pontoons, and passed across over the wreck. These beams were double, con- 

 sisting each of two pieces, each piece 18 in. by 9 in., placed five inches apart, 

 and bolted together in three places by three-quarter inch bolts. 



The length of the beams was from 48 feet to 53 feet, according to position. 

 They were of Kahikatea, or IS". Z. white pine. They proved strong enough 

 for the strain, but with nothing to spare, deflecting a foot in the middle when 

 the strain came on them. Two of them sprung in the early part of the 

 work, but they were of lighter scantling, and were strengthened and used 

 afterwards. 



On each of these beams, and over the inner side of the pontoons so as 

 to plumb the sunken vessel's sides, were placed two blocks of hard wood 

 (Rata), each 15 in. by 5 in., and 2 feet long, with a hole 5 inches square for 

 the lifting rod to j)ass through, and on this block was placed the plate, or 

 washer, already described, carrying the upper washer and nut of the lifting 

 screw. (See sketch.) 



On an average, fifty-four men were employed. 



The mode of screwing up a lift was, first to screw up all the screws on 

 one side for one foot, or half the length of lift, then proceed to the other side 

 and screw up two feet, or the full length of the lift, and then go back to the 

 first side, and screw up the remaining half of the lift for this side. 



The mode of fleeting the screws was, to begin to fleet simultaneously the 

 foremost screw on each of the two pontoons upon one side, and the after- 

 most screw on each of the two pontoons on the other side; and then, when these 

 had been adjusted and were being tightened up, the screws next but one to 

 the four already fleeted were slacked off, and so on, till all the screws were gone 

 through and got ready for a fresh lift. Thus no one log had the strain taken 

 off both of its ends at one time. In this operation eight sets of lifting rods 

 were relieved of the weight at one time, and the weight of the wreck was then 

 borne safely by the remaining thirty-six rods. 



They could fleet and screw up twice in one day, taking about an hour to 

 fleet, and three hours to heave up a lift. 



Two divers were employed, who had the arduous task of fixing the hooks 

 under such a depth of water, opening the ports, cutting away the woodwork, 

 and other jobs, such as sending up the anchors and chains, etc. 



Their labour was much facilitated by the use of a box, or cage, 6 feet by 



