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its bed, the Ohinemuri has been laden as a sludge-channel by exceedingly large volumes of mining tailings, the greater portion of which has been deposited in its bed from Mackaytown to a point some six miles lower down, and which point is about three miles up from the Junction. Deposit of tailings. Below this point, so far as the evidence shows, there has been no serious deposit of tailings in the mid-stream bed of the Ohinemuri, but successive floods and freshes have deposited tailings and slimes to a very considerable extent on the banks of the Ohinemuri down to the Junction, and on the banks of the Lower Waihou for very many miles below the Junction, as well as upon the flooded lands. Natural floods. It is clear that, whilst both the Waihou (Upper and Lower) and Ohinemuri Rivers have always been subject to considerable floods, being only laden with good alluvial deposit, they did no permanent harm to any lands that were flooded; but, owing to the restriction of the waterway by growth of willows, and to its reduced section by the deposit of artificial sands on its bed and banks, the River Ohinemuri, and the Lower Waihou to a lesser extent, are now incapable of carrying off the volumes that they ought to convey; with the result that the freshes and floods are becoming more numerous, and of a higher and more disastrous character; and, being now laden with injurious mining slimes and sands, there has been caused a material loss to the owners of flooded lands. It is also probable that, as the settlement of the river-flats has increased materially since the rivers have been used for sludge-channel purposes, and as the values of the lands have increased so largely through the growth of the dairying industry, the effect of the floods is more noticed than it used to be when the population was sparser. Tidal limits.—Extent of tailings, Waihou. The Ohinemuri River for about two miles above Paeroa Township, and the Upper Waihou for some five or six miles above the Junction, are tidal. At and below the Junction there has been considerable shoaling in the Waihou River, largely due to artificial works, and the Lower Waihou shows the presence of mining-silts on its banks to a greater or less extent as far north as the mouth of the Hikutaia Creek, near the northern limit of the Ohinemuri County. The Lower Waihou is in many places materially narrowed and pinched in consequence of the deposit of artificial sands; and the navigable channel has in places become narrower from the deposit of sands, though not necessarily of mining origin. Limits of Ohinemuri boundary. Within the boundaries of the Ohinemuri County—that is, from about one mile below the mouth of the Hikutaia Creek for about twelve miles up to the Junction, and up to a point near Te Aroha about eighteen miles above the Junction—the Lower and Upper Waihou Rivers, and the whole of the Ohinemuri River, are nominally under the control of the Ohinemuri County Council, acting as a River Board. Limits of Thames County jurisdiction and Thames Harbour Board From the northern boundary of the Ohinemuri County, for a distance of about five and a half miles, down to the southern limit of the Thames Harbour District, there is, so far as we could ascertain, no local authority having jurisdiction over the river, unless it be the Thames County Council. For the balance of its run to the Hauraki Gulf the Waihou River—which seems here to be, by o-eneral consent, called the Thames River—is within the jurisdiction of the Thames Harbour Board. The banks of the Lower Waihou, and of its tributary, the Komata Creek, are burdened with a growth of willows, but not to so serious an extent as in the Upper Waihou or Ohinemuri Rivers.