Overview
Sun. Jan. 9.
Up at 4 a.m. – Left at 5.am route for Mangahao (7th visit,
[page break]
in gig driving Silvermane. Passed Buckley Rd at 6 am. + the corner at Shannon at 6.15. A cloudless sky + Hazing hot later. Reached Mangaore Bridge at 6.40 + left horse + gig inside gate at “1st House” at 7 a.m. Proceeded on foot, ascending Te Paki Ridge via the track up spur + reached timber tram saddle at 9.42. Took 10 minutes spell here + passed through Main Camp at 8.5. Followed service road. ¼ pl[ate] photo (1) of sunlit bush alongside service road looking NE. ½ pl. (2) looking down jig -tramway to Mangahao River. ½ pl (3) telephoto of reach of Mangahao just above future tunnel entrance from near top of jig tramway. In this view the end of the track on left is exactly opp[osite]. the tunnel entrance. Descended zig-zag track + reached No.1. Gorge at about 9:30 a.m. ½ pl photo (4) looking down into No.1 Gorge from left bank above future dam site. ¼ pl. (5) the powerhouse looking upstream from same spot. The suspension bridge across the gorge is 110ft in length + average width of gorge is about 15 yards. Found only one party at work at test-shafts – Messrs Kyle + Gunton + had a long chat with former. He told me that originally the engineers
[page break]
thought that solid rock would be found at a depth of 12ft right across the top of the high-level terrace – that the line of the dam was changed when test-pits along the original line showed that a great depth of shingle + boulders existed. By moving the line of the dam, a little upstream, the deep shingle +c was expected to be avoided. This of course did not come about. It is evident that the terrace was thought to be a cut rock-terrace capped by about 12ft of river-deposited detritus + presence of the old valley parallel to the present gorge was not suspected. Even now the true structure of the Mangahao Vally [sic] at this spot does not seem to be clearly known to the engineer's + it is evident that a great deal of money will be wasted that could be saved if my theory were adopted + put to the test. By means of Abney’s level + pacing the distances I made a careful section of No.1 Gorge
[sketch follows here]
[page break]
getting details shown in the accompanying section. Had a snack with Kyle + Gunton having left my lunch at home. Left Mangahao 11.45. At Hilltop camp had a talk with Mr Roach, assistant engineer at Mangahao Gorge, re[garding] structure of gorge but he refused to give me any information re the official idea of the structure at No1 Gorge + referred me to his chief Mr Johnson upon whom however I did not have time to call. Passed through main camp at 1:15 + had a chat with Mr Miller, assistant-engineer at the Arapeti. ½ pl[ate] photo (6) looking down to Arapeti dam-site from old timber trimline. Crossed ridge + got back to gig at 2:30pm. ½ pl photo (7) of head of Shannon East Rd showing temporary powerhouse + other buildings (general view) + Te Paki trig. Home at 4:50 p.m. Drove to church in the evening in Cheslyn Rise car. Temperature today in shade 82°