The first experiment to which I shall refer was made on wells situated comparatively close together. Bore No. 5 is 570 metres W.S.W. of Bore No. 6, the outlet of the former being at 57·38, that of the latter at 59·18, a difference of 1·8 metres. No. 5 has an internal diameter of 5⅝ inches, is 197 metres deep and 95 metres into the water-sandstone; No. 6 has a diameter of 8 inches, is 146 metres deep, and 61 metres into the sandstone. The two wells had been flowing continuously for a considerable period, and during the experiment neighbouring wells were kept shut down, so that there is no reason to suppose that the observations were affected by other bores. Bore No. 5, discharging 114 gallons a minute, was shut down at 7 p.m. on June 12, 1907, and reopened at 7 a.m. on June 13. The hourly observations, as given in the following table, show the effects produced on Bore No. 6. EXPERIMENT TO SHOW MUTUAL INTERFERENCE OF BORES. +-------------------------------++-------------------------------+ | Bore No. 5 closed at 7 p.m., || Bore No. 5 opened at 7 a.m., | | June 12, 1907. || June 13, 1907. | +-----+---------+-----+---------++-----+---------+-----+---------+ |Time.|Discharge|Time.|Discharge||Time.|Discharge|Time.|Discharge| | | of Bore | | of Bore || | of Bore | | of Bore | | | No. 6. | | No. 6. || | No. 6. | | No. 6. | +-----+---------+-----+---------++-----+---------+-----+---------+ |P.M. | Gallons |A.M. | Gallons ||A.M. | Gallons |P.M. | Gallons | | | per | | per || | per | | per | | | Minute. | | Minute. || | Minute. | | Minute. | | | | | || | | | | | 7.0 | 61·2 | 1.0 | 76·6 || 7.0 | 83·7 | 1.0 | 69·0 | | | | | || | | | | | 8.15| 65·6 | 2.30| 77·4 || 8.0 | 78·4 | 2.0 | 67·7 | | | | | || | | | | | 9.0 | 68·4 | 3.0 | 79·2 || 9.0 | 75·0 | 3.0 | 66·8 | | | | | || | | | | |10.0 | 69·6 | 4.0 | 79·7 ||10.0 | 73·0 | 4.0 | 66·2 | | | | | || | | | | |11.0 | 73·2 | 5.0 | 82·1 ||11.0 | 70·8 | 5.0 | 66·6 | | | | | || | | | | |12.0 | 74·7 | 6.0 | 83·1 ||12.0 | 69·6 | 6.0 | 65·3 | | | | | || | | | | | | | | || | | 7.0 | 64·0 | +-----+---------+-----+---------++-----+---------+-----+---------+