115Mr. REDHAN described the spring tides of the 15th and 16th of March, 1877, a t Sheerness and at London, the high-water difference being 4 feet, and the low-water difference 34 inches, and lowest a t Sheerness (Plate 3). The mean half-tide range or axis of the tidal column having a fall of 2 feet 2 inches. High-water in London corresponded with two and a half hours ebb a t Sheerness, where there was 8 feet fall in the surface of the water, equal to 2 inches per mile over 48 miles. Conversely, when low-water i n London it was two and a half hours flood a t Sheerness, with 6 feet fall upwards, equal to I* inch per mile, the intermediate stages of tide being shown by lines of equal times connecting the two tidal curves. His acknowledgments were due to the chief officers of the ' Hydrographical Department of the Admiralty, of the Ordnance Survey at Southampton, and of the London Docks, without whose generous and ready assistance he could not have attempted the task he had essayed.
Mr.0. E. ~P E ,M.P., said,as representing the county of Middlesex, he had taken a great deal of interest in the floods of the Thames, and 6he best mode of preventing them. He had been somewhat surprised to learn that there was a difference of opinion among professional men with regard to the contraction of the river. His own impression was that by contracting the river by embankments the tidal water at high tides, and with favourable winds, was made t o flow over the banks ; but he also believed-although he was quite open to correction on this point-that these frequent floods might be attributed to the great surface drainage that had been carried on of late years. These two causes might account for the floods which now seemed to be almost periodical.There was no doubt the more the land was drained the more rapidly was the water brought into the river, and the smaller was the reserve for the drier months. The consumption of water was, of course, rapidly increasing with the increase of the population of the zlletropdis, and it had been his belief that one mode of remedying the floods and keeping the storage of water would be by erecting large reservoirs to receive the faters in times of flood, and to give them off when required in the drier seasons. He felt exceedingly indebted to the Author for this valuable Paper, which contained so many facts connected with a river that every Englishman must take the greatest possible interest in-the most valuable river, in many respects, in the world. He had a motion for next month in the House of Commons to consider the question of the floods in the Thames, especially as regards the action of the Thames Conservancy in preventing those floods.
