INDUSTRIES 



According to Morton, slates were also obtained 

 from Pitsford, Weston Favell, and Pytchley. 



CoLLYWESTON Slates. — The term Colly- 

 weston slate is given to a fine-grained, calcareo- 

 arenaceous rock occurring at the base of the 

 Lincolnshire limestone. It is found and has 

 been worked at other places besides CoUyweston, 

 such as Kirby and Easton, between CoUy- 

 weston and Stamford. The quarries at and 

 near CoUyweston have been worked from very 

 early times, and at the present time furnish a 

 considerable share of the employment for the 

 inhabitants of that village. 



The methods of extracting, splitting, and 

 finishing the stone are interesting, but can only 

 be very briefly referred to here.^ There is only 

 one bed of stone yielding slates, but it varies in 

 thickness from 6 in. to, in rare cases, 3 ft., or 

 its place may be entirely occupied by sand. 

 It is worked in open quarries, or in ' fox-holes,' 

 i.e. long galleries underground, in the winter, 

 December and January, both to avoid the 

 trouble with water in the adits which would 

 occur later on, and to take advantage of the 

 frosts and thaws of the early part of the year to 

 split the stone. The blocks of stone are spread 

 out on the ground, and they must not be allowed 

 to get dry before the frost acts on them, and so, 

 if necessary, they are regularly watered up to 

 about March. If the quarry-water once dries 

 out of the stone no artificial wetting afterwards 

 is of much use, and the stone is then ' stocked ' 

 and used for road metal. The stones are of course 

 split by the freezing of water along the planes 

 of bedding, and the cleaving of them afterwards 

 by the workman is easy, though requiring skill. 

 Dressing and trimming follow the splitting, and 

 the slates are stacked in different sizes. 



The CoUyweston stone is mostly blue-hearted, 

 and so the slates are often parti-coloured, yel- 

 lowish, buff, and blue, but they gradually become 

 more homogeneous in colour on exposure on a 

 roof. The slates look very nice when covering 

 a stone building, whether white stone or red. 

 As examples of red stone buildings covered with 

 them may be mentioned St. Sepulchre's Church, 

 Northampton, and the recently-erected Weston 

 Favell House, near Northampton. 



The slates are fairly durable when carefully 

 selected, but they should always be fixed with 

 mortar or cement as well as pegged, so that they 

 <lo not fall away if cracked. The usual plan is 

 to use the largest slates for the eaves of the 

 building and then regular lines of diminishing 

 sizes to the ridge ; the ridge itself being formed 

 of special tiles of a yellowish white colour, made 

 at Whittlesea. 



A few old CoUyweston slate roofs may be 

 observed in ancient Northampton buildings, and 

 quite a large number of buildings in the towns 



' For fuller description, see Woodward, Jurassic 

 Rocks of Britain, iv, 482. 



and villages of north-easterly Northamptonshire. 

 This is one of the few building materials re- 

 gularly sent out of the county to distant places. 



The slaty beds of the Lincolnshire Oolite, 

 where not suitable for slates, known as ' Pendle,' 

 are sometimes used for paving, walling, and other 

 purposes ; such have been worked about Cotting- 

 ham and Whittering (Whittering Pendle). 



BRICKS AND POTTERY 



Bricks have been and are now made at quite 

 a large number of places in Northamptonshire, 

 though the tendency is for the number of places 

 where they are made to diminish. Indeed, the 

 introduction of modern methods of manufacture 

 necessitating much machinery and power has 

 practically shut up all the smaller brickyards 

 where barefooted men and boys dug the clay, 

 wheeled it in hand-barrows to and from the 

 moulding-bench, and splashed themselves from 

 head to foot as they dabbed the wet clay into 

 the mould and made one brick at a time. 



Only red bricks are produced from the blue 

 (ferruginous) liassic clays of Northamptonshire ; 

 but of course blue bricks can be, indeed they 

 have been, produced ; and some of the oolitic 

 clays will produce a white or very light-coloured 

 brick. White bricks are made at Eye fi^om the 

 Oxford clay. 



Within the writer's memory, Lower Lias clay 

 has been worked for brickmaking at Braunston, 

 Welford, Buckby Wharf, and Marston Trussell ; 

 but none of these brickyards, unless possibly the 

 last-named, are now in work. 



Bricks have been made from the sandy cal- 

 careous clays of the Middle Lias at Watford and 

 Crick, but the Watford works have been closed 

 many years. These loamy clays are on the 

 whole rather good for brickmaking, and the 

 finely divided calcareous matter is no objection, as 

 it acts as a flux to the silica in burning, and so 

 helps to produce a good hard brick. It is also 

 said to diminish the contraction of the new brick 

 in drying. More than a certain amount of 

 calcareous matter in a clay, however, altogether 

 destroys its use for brickmaking. 



The number of places where Upper Lias clay 

 has been worked for brickmaking is very large, 

 but it will suffice to say that more or less ex- 

 tensive works now exist at or near Easton Neston 

 (Towcester),^ Blisworth, Gayton, Heyford, 

 Northampton, Wellingborough, Rushden, Irth- 

 lingborough, Kettering, and Corby. 



TheLowerand Upper Lias claysalways contain 

 argillo-calcareous nodules, which if left in would 

 burn to lime, and ' blow ' the brick afterwards 

 when it got wet. In most cases the nodules are 

 moderately large and easily picked out of the 

 clay as it is worked up ; but in other cases, 



' Recently closed. 



303 



