CENTRAL OTAGO

Otago Daily Times, Issue 21981, 16 June 1933, Page 12

CENTRAL OTAGO

CROMWELL NOTES

(From Our Own Correspondent.) CROMWELL, June 14. NEW MINING DEVICE. Successful beyond expectations was the unanimous verdict of the pantentee and a gathering of nearly 100 miners, farmers, and business men who, on Tuesday afternoon, witnessed the first public demonstration of Mr R. S. Cree Brown’s latest system of siphon, designed to divert and automatically control a large and fluctuating body of water. The origin of the local demonstration was in representations made by a local mining syndicate to Mr R. Cree Brown for a scheme for de-watering, in sections of 1000 feet, some eight miles of the famous Nevis River gorge from the Kawarau to Nevis Crossing. The advantages of the siphon "were put forward, but so great were the claims of the patentee that a demonstration was asked for and readily agreed to at the expense of the patentee, A working model six inches in diameter was constructed 42 feet in length and set in a branch of the Lowburn Creek, with 16 inches of fall in its entire length. The siphon was laid at a level of two feet above the flow of the creek water, only the inlet and outlet being set in the stream. To extract the air from the siphon to create the flow of water a small Stephens patent pump was placed in operation in the main creek. With only a temporary structure and several joints the siphon was not immediately cleared of air. The early flow of water was less than a quarter of a head, due to an air pocket, and naturally a few were sceptical. However, the flow of water through the pipe gradually absorbed and automatically reduced the air lock until it was finally cleared, and the siphon, by actual measurement was diverting one and onetenth heads of water. The patentee’s previous claim was for slightly less than one head. The flow to the siphon was reduced to about one-fifth of its full capacity, but the work of the siphon continued without interruption by reason' of the automatic control at the inlet. An interesting description was given by the patentee, who also answered questions. It was one of the most successful demonstrations of the kind ever held in the district, and proof of this lies in the fact that later in the day the members of the syndicate, with less than 10 minutes’ discussion, unanimously adopted and signed a contract for the system for their claim. The inlet and outlet sections are known as “ swan necks,” and these are the only parts actually set in the flow of a stream. The siphon is established above flood level, and in such an emergency the swan necks can be swung back above the height of the main line and lowered again into operation as the flood subsides. The siphon of 1000 feet would be in operation within three hours of placing the ends in the water and have the bed of any stream clear of water. It opens up new possibilities in the de-watering and mining of streams.