The following notes record some of the features of interest seen by visitors to collieries, works, etc., which were, by kind permission of the owners, open for inspection during the course of the Newcastle-upon-Tyne meeting on September 16th, 17th, 18th and 19th, 1902:—

The first sod of the Theresa or south shaft was cut by the Marchioness of Londonderry, and the first sod of the Castlereagh or north shaft by Viscount Castlereagh, on August 26th, 1899.

Sinking operations commenced on April 17th, 1900.

Both shafts will be 20 feet in internal diameter when completed.

Theresa Pit. — The Theresa shaft is now 350 feet deep, and has 225 feet of cast-iron tubbing, and 96 feet of brick lining in it. The largest feeder yet met with in this shaft was 6,075 gallons per minute, at a depth of 196 feet from the surface.

The ground sunk through in this pit is as follows :

Thick- Depth

ness of from

No. Description of Strata. Strata. Surface.

Ft. In. Ft. In.

1. Soil 1 0 1 0

2. Strong clay 5 0 6 0

3. Sand and gravel 3 0 9 0

4. Marl with limestone-panels 6 1 15 1

5. Marl 22 6 37 7

6. Limestone 6 0 43 7

7. Strong marl 66 0 109 7

8. Strong marl, in blocks 64 8 174 3

9. Hard limestone 60 6 234 9

10. Grey marl 4 7 239 4

11. Grey limestone 73 4 312 8

12. Grey and yellow limestone, into 37 4 350 0

Several small bore-holes have been put down from the bottom of this pit, and it has been found that the sand lies 19 feet below the present pit-bottom. The sand is 84 feet thick. It is thought that the sand is somewhat solidified, and that it will be sunk through without much trouble.

In this shaft there are pumps capable of delivering 7,000 gallons per minute, namely :— Two 24 inches and one 25 inches pumping sets, and two vertical sinking-pumps, with cylinders respectively 24 inches and 16 inches in diameter by 24 inches stroke, each capable of pumping 1,000 gallons per minute from a depth of 300 feet.

Sinking operations in this shaft have been suspended until the north pit reaches the same depth, so as to permit of both shafts being taken through the sand together.

Castlereagh Pit. — The Castlereagh shaft is at present 190 feet deep. It bas the same amount of brick lining as the other shaft, but has only one lift of tubbing, 33 feet long, completed. At present, another lift of tubbing, 53 feet high, is being inserted. The present feeder is the greatest yet met with, amounting to 4,480 gallons per minute.

The section of this shaft is:

Thick- Depth

ness of from

No. Description of Strata Strata. Surface.

Ft. In. Ft. In.

1. Soil 1 0 1 0

2. Clay 5 6 6 6

3. Sand and gravel 4 6 11 0

4. Strong marl, with limestone 50 10 61 10

a. Limestone, with marly partings 32 7 94 5

6. Marl, with gullets 90 0 184 5

7. Hard limestone, into 5 7 190 0

To clear the water from this pit, a drift has been driven from the Theresa shaft in a northerly direction, and a bore-hole, lined with steel tubes 9½ inches in internal diameter, has been put down into this drift, and the water, which runs downward, is pumped at the Theresa shaft. There is also a sinking-pump, similar to those in the other pit, hung in this shaft to pump the excess-water, which the bore-hole cannot drain off.

The water in both shafts is pumped into a drift, 90 feet below the surface, from which it runs to the sea-beach.

It is proposed, when the Castlereagh shaft reaches the same depth as the Theresa shaft, to put in four 30 inches sets of pumps — two standing sets and two sinking sets — for pumping the water, while going through the sand.

Engines, etc. — The sinking-engines have each two cylinders 24 inches in diameter, and a stroke of 4 feet. The drum is 6 feet wide, and 8 feet in diameter. The locked-coil rope is 3¾ inches in circumference. These engines will eventually be used as underground hauling-engines.

The pumping-engine for working the two 24 inches sets and one 25 inches set in the Theresa shaft has two cylinders, 36 inches in diameter and a stroke of 6 feet, and the flywheel is 24 feet in diameter.

The main crab-engine has two cylinders, 14 inches in diameter and a stroke of 8 feet it is geared 10 to 1, and the rope is 6½ inches in circumference. The cylinders of the ground crab-engine are 8 inches in diameter and a stroke of 14 inches it is geared 30 to 1, and works with a rope 5½ inches in circumference.

The foundations, 4½ feet thick, of the permanent winding-engine houses have been built, their outside measurements being 66½ feet by 48½ feet, and 23½ feet deep.

The permanent winding-engines will be of the Corliss-valve type, with cylinders 40 inches in diameter, and a stroke of 6 feet, and the drum will be 10 feet wide and 20 feet in diameter.

An engine is used for compressing air to drive the rock-drills used in the bottom of the pit.

Boilers, etc. — There are 8 Galloway boilers, each 30 feet long and 8 feet in diameter, fitted with two furnaces, 3¼ feet in diameter, working at a pressure of 100 pounds per square inch There are also 3 locomotive-type boilers, but these are not being used at present.

There are four sets of Green fuel-economizers of 120 tubes each. The gases enter the economiser-flues at a temperature of 500° Fahr. and leave at 300° Fahr., and the water enters the economisers at 85° Fahr. and leaves them at about 240° Fahr.

The chimney for the Galloway boilers is 160 feet high, its base is 24 feet square, and the inside diameter at the top is 12 feet.

There are two water-softening tanks, each 15½ feet by 15½ feet by 10 feet deep, holding 15,000 gallons each, and capable of treating 60,000 gallons per day. The water for boiler-feed purposes is softened in these tanks by the Archbutt-Deeley process, and the hardness, which is originally about 16 degrees, is reduced to 4 or 5 degrees. About 40 pounds of lime and 7 pounds of alkali are used for each tank treated, at a cost of about 0.46d per 1,000 gallons.