Looking Down on Arapuni

Sun (Auckland), Volume IV, Issue 1006, 24 June 1930, Page 8

Looking Down on Arapuni

VALUE OF AERIAL PHOTOGRAPHY

HAD aerial photography been considered in the early stages of investigation at Arapuni, the present unsatisfactory situation which is exercising the minds of engineers and geologists might possibly have not arisen. An “X-ray” of the whole area, and such could have been provided by the new science of survey from the air. would have provided a more comprehensive knowledge of irregularities in the earth’s surface, and thus have given assistance in obviating' trouble.

How one can see into the ground from the airplane forms one of the most romantic chapters in the very modern science of air surveying. The airplane lias handed to science the key to a new and thrilling corridor of discovery into the secrets of the vanished past. Lost cities and the cultivation systems of foi'gotten peoples have been discovered. While the spade of the excavator fumbles blindly, guided by an instinct which is so often wrong, the airplane has given to the archaeologist something equivalent to the X-rays of the surgeon.

But this modern marvel is bound up with the development of something hardly less exciting—the science of air surveying. It is an established fact that one can see from the airplane for a remarkable depth into the waters of the sea. During the war the submarine, invisible to observers on ships, was detected from the air, but few can realise that it is possible to peer into the earth. Yet, it is well proven, and while air surveying has but a short history, it has indeed an immense future, and the fine work already accomplished has indicated its invaluable use to science.

The significance of the new instrument which the mastery of the air has put into our hands was hardly realised in New Zealand in the early stages of investigation at Arapuni, although, at the time. Air Force planes were busily engaged in surveying and map-making in the South Island. While the dam site at Arapuni was thoroughly investigated by means of geological examination and found to be sound, it was, of course, an impossible task to take borings over the large surrounding area. But the general assumption was that the same geological strata obtained at the dam would be found within a fair radius.

Had aerial photographs been taken on the whole area, it would have actually “blown to pieces’’ any false assumptions, and the various phases of formation around Arapuni would have been clearly indicated. From a large photograph which would have been the result of many smaller ones pieced together, one would have seen the buried forest. the meandering track of the river-bed, the erosion on the rocks and many things, all of which may have happened thousands of years ago before the river finally settled on its present course. And such a knowledge at the outset of the

work at Arapuni might have been of inestimable advantage.

The airplane can do in a few hours what the earth-bound surveyor would take weeks to do, and in some cases can carry out work which, in the ordinary course of events, would take decades to do. There is yet but a ha zv idea of the Dominion's natural resources, yet the airplane could show what exploitable wealth there is. And the knowledge is brought —rapidly and easily acquired—of the exact extent of trackless forests and grasslands, the course of rivers, the emergence to the surface of rocks, and so on. But that one should be able to pierce below the soil and discover the relics of the past, 'even though so true, may seem apocryphal. Major Cochran-Patrick, of the British Aircraft Operating Company, once said:

“We see the face of the country scarred by the traces of a civilisation whose very existence we might not suspect if we remained on the ground. Roads spring into sight, forts, villages, fields, cultivation terraces — there they are where before we only saw the clean white modern roads, the brick farmhouses which may be as old as the Tudors, but yet mere parvenus compared with the infinitely more ancient things below. We can, literally, look below on modern England and see an infinitely archaic England breaking through.” The history of the aerial branch of archaeology is quite brief. During the war the Germans made some excellent air photographs of the Sinai Peninsula, where they discovered the sites of lost cities and saw in the shadows cast upon the sand, gardens, courtyards. streets and churches. It was not until later that the science was taken up in Britain and subsequently in the Dominions. In England one of the most remarkable discoveries was of the hill-fort at Woodbury, in Wiltshire, of which nothing at all could be seen on the ground to justify the belief that early men had settled or built there. But the air-eye revealed a dark band, with two lighter bands on either side and the traces of the old fort were plain to all. Sites of ancient cultivation systems were found in many districts where their existence had not been suspected. A modern golf course was found to be the scene of a most elaborate group of fields. The bunkers and greens were clearly seen, but no less clear were the lines of an old camp’s ramparts and the earth wall between the vanished fields.