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traffic. These sands are thus referred to in the Cottonian MS., 

 as quoted in Graves's ' History of Cleveland,' p. 399: — ' From the 

 passage of the sands, by Reason of the Fyrmenesse and Smooth- 

 nesse frequented by such as delight in Swifte Horses, you next 

 come to Redcarre, a poor fysher Towne.' The Tees Conservancy 

 Commissioners have erected a magnificent breakwater at Tod 

 Point, on the south side of the river, and are now erecting 

 another on the north side. This, when complete, will leave the 

 entrance to the river about 700 yards wide. From this break- 

 water to Middlesbrough there is an area of between 5,000 and 

 6,000 acres, between the high-water embankments of the Tees 

 Commissioners, which is covered at high tide only, except the 

 channel ; the greatest extent of mud-flat is on the north side, 

 and is called Seal Sand ; that on the south side is called Bran 

 Sand. Geologically, the basin of the Tees may be said to consist 

 principally of Boulder Clay, with detached patches of an estuarine 

 deposit of sand and gravel in places — the old part of the town of 

 Middlesbrough being built on one of these. Under the Boulder 

 Clay is found the New Red Sandstone ; and below this again, at 

 depths varying from 1,000 feet to 1,500 feet, has been found a 

 bed of rock salt, about 100 feet in thickness, and underlying the 

 town of Middlesbrough and adjacent district. It will probably 

 be found to form a kind of basin, and to cover no very extensive 

 area ; yet, taking into consideration its great thickness and its 

 quality, it may reasonably be expected to give a great impetus to 

 the town and trade of Middlesbrough and district, with the 

 development of the chemical trades connected with it. It is now 

 being pumped up in the form of soluble brine in one or two 

 places on the north side of the river, and has been reached at 

 boreholes on the south side of the river at Middlesbrough and 

 Eston. The method of raising the salt is thus described in a 

 paper on ' The Iron Trade of Cleveland and the Industries of 

 Middlesbrough,' by Sir Isaac Lowthian Bell, Bart., published in 

 a handbook of Middlesbrough and district: — ' A tube, 16 inches 

 diameter, is carried from the surface to the bottom of the bed of 

 salt — the portion which traverses the salt being pierced with 

 holes. Inside this a second tube is placed, open at the lower 

 end. Water is run down the annulus formed by these two tubes, 

 and, becoming saturated with salt, rises in the internal tube 

 until it is balanced by the outer column of fresh water. The 

 proportional weight of fresh water and brine is as 1,000 is to 

 1,200, so that the inner column stands considerably below the 

 outer. A pump is placed at the top of the inner column, and by 

 this means the brine is raised to the surface.' 



