Page:Transactions of the Natural History Society of Northumberland, Durham, and Newcastle-upon-Tyne (1867).djvu/48

32 The Boulmer Dike is 100 feet wide, ranging north 80° east, and appears only on the coast passing perpendicularly through Mountain Limestone strata, which it has altered but slightly.

Trobes Dike is seen in the eastern part of the Shilbottle colliery, running in the direction of south 85° west, having a width of 33 feet, and metamorphosing the strata on both sides.

The Hampeth Dike is large, and passes through the Shilbottle coal field. A mile and a half south-west of Shilbottle it appears in the bed and banks of Hampeth Burn, which has forced a pass through this rocky barrier by a narrow gorge, the basaltic cliffs on both sides reaching the height of 50 feet. The width of the dike here is 150 feet, and the direction S. 80° W.: near to it the coal is charred. It seems to extend to the sea, passing through Millstone Grit beds a little southward of Berling Carr.

The Acklington Dike has a general direction of west by north, and appears on the coast at Bondicar; passing through the Coal Measures and Millstone Grit, it crosses the Coquet near to Acklington Park, where it is 30 feet wide. A dike in the line of this is seen cutting through the Mountain Limestone, at Debden colliery, and ranging onward as far as Clennell approaching near to the porphyry of the Cheviot, but never entering it. At Cartington Castle a limestone abuts against it on the north side. The range is thus about 20 miles.

The Causey Park Dike is 30 feet wide, and has a direction from east to west, cutting through Millstone Grit strata. Gritty sandstone abuts against the north cheek, and flaggy sandstone and carbonaceous shale are on the south side.

Two dikes, about a mile and a half apart, run parallel from Hartley to a mile northward of Cramlington, in the direction of west north-west, and pass through Coal Measure strata. In a line with the Southern Hartley Dike is one at Bolam cutting through Mountain Limestone beds, which are metamorphosed.

The Tynemouth Dike appears in the cliff below the Priory, rising through the Coal Measures, the red sandstone, and the