Dearie:Russell Family History

Malayan Collieries, Ltd. (incorporated in F. M. S.) A BRIEF DESCRIPTION OF THE PLANT AND ACTIVITIES AT BATU ARANG AS A GUIDE TO VISITORS. Printed by Charles Grenier & Son, Ltd., K.L. (incorporated in F. M. S.)

1. A BRIEF DESCRIPTION OF THE PLANT AND ACTIVITIES AT BATU ARANG AS A GUIDE TO VISITORS- A brief description of the plant and activities At Malayan Collieries, Limited Batu Arang Selangor F.M.S. -

The entire property covers an area of 9,000 acres of which nearly 2,000 acres are occupied by plant and surface workings and garden plots of the labour force. In normal times a labour force of about 3,000 is employed, while the total resident population ranges between 4,000 and 5,000 souls.

The coal extends throughout the property and occurs in two seams each varying in thickness from 20 feet to 40 feet.

The deposit which is of Tertiary age is classed as a high grade lignite or sub-bituminous coal and the properties are indicated by the following proximate analysis of coal as delivered to consumers:—

Moisture 21% Ash 9% Volatile Matter 35% Fixed carbon 35% Calorific value "as received" .. 9,000 B.Th.U. per lb "dry coal" 11,000 "dry ash free" .. . . 13,000

The coal output from all sources is sampled at regular intervals and analyses and determination of calorific value are carried out as part of the routine work of the Service Department in charge of a Combustion Engineer at Head Office.

The coal is usually worked by means of two deep mines entered by inclines, and four Opencast mines, and the possible monthly output is in the region of 100,000 tons, but owing to the restricted output as the result of present trade depression only one deep mine and one opencast are being worked regularly. Other workings, however, are ready for immediate use and can be brought into commission to meet any increased demand.

The Company have provided and operate a system of standard gauge railway, having a total length of about 12 miles which runs throughout the Colliery area, and is the means of conveying the coal from the various workings to the main line, after passing over the F.M.S. railways weighbridge immediately before despatch.

The operations are now electrified throughout, electrical power for all purposes, being generated in a central station and transmitted to the various consuming points, partly by overhead and partly by underground cables. In all there are about 100 motors connected up, the aggregate H.P. being approximately 4,000.

POWER. The power house contains the following plant:—-

2 Metropolitan Vickers Steam Turbo Alternators each 2,000 K.W., 3,000 Volts, 3 phase, 50 cycles.

2. The machines are entirely self contained. The turbine which is superposed on the condenser, runs at 5,000 r.p.m. and drives the alternator, exciter, circulating and condensate pumps at 1,000 r.p.m. through 5 to 1 single reduction helical gears.

1 Belliss and Morcom-B.T.H. reciprocating Set, 400 K.W. 3,300 Volts, i 3 phase, 50 cycles, 375 r.p.m.

To serve the D.C. demand there is:—

1 English Electric Reversible motor generator, synchronous speed 1,000 r.p.m. 3,300 Volts, 3 phase, 50 cycles, on the A.C. side and 500 Volts on the D.C. side.

augmented with:— 3 Browett Lindley reciprocating Sets each 300 K.W., 500 Volts D.C, -360 r.p.m.

All the reciprocating sets are non-condensing, this being due to the shortage of circulating water until the recent tapping of a source which ensures an ample supply of water for condensing purposes.

MAIN CONTROL AND DISTRIBUTION BOARDS. The A.C. gear by Reyrolle & Co. Hebburn-on-Tyne, fitted with modern protective devices, is installed on a raised gallery in the power house and comprises:—

9 iron clad, compound filled type oil circuit breakers each with rupturing capacity of 75,000 K.V.A. 3 Neutral Earthing Switches, oil immersed type direct operated and suitable for 120 amps., 2,200 Volts, single phase. 3 Exciter cubicles and voltage regulators, complete with relays and meters. 1 Synchronising Panel complete with illuminated dial volt meters and frequency indicator.

The Main Switch Board for the D.C. side is situated at the floor level and comprises the following:—

4 Incoming panels fitted with single pole maximum, reverse current circuit breakers connected to 500 Volts main bus bars. 9 Outgoing panels fitted with double pole quick make and break knife switches and fuses each capable of carrying 300 amps.

There are also two switch cubicles on floor level which interconnect the A.C. and D.C. sides of the plant through the Motor Generator.

SPRAY COOLING EQUIPMENT. This includes a concrete pond 150' x 120' x 4' deep with an approximate capacity of 450,000 gallons. The pond is connected with the power house by a system of pipes and a concrete culvert. The banks of sprays are by Messrs. Bullocks & Co., London, and at the present time they handle about 3,500 gallons of water per minute although they are designed to deal with eventual extension to three times this quantity.

The cooling effect of the sprays is approximately 10°F although with the present low load the temperature difference between the inlet and outlet water is only about 4°F. and the daily make up is at present less than one half of one percent of the water in circulation. The pond and spray banks are divided into two sections and so arranged that either or both sections can be used at a time. This arrangement was found necessary in order to combat the algal growth that takes place on the walls and pillars of the pond and which, prior to the sectionalising of the pond, necessitated shutting down the plant periodically in order to clean out the growth and prevent inadvertant shutting down as the result of fouling of the circulating water screens. Before sectionalisation was resorted to a wide range of chemical treatments was tried but none was found to be successful.

3. BOILER HOUSE. The existing installation in the Boiler House comprises:—

3 Babcock & Wilcox W.I.F. type, Double Drum Water Tube Boilers equipped with Mechanical chain grate stokers and integral superheaters, each unit having an evaporative capacity of 9,000 lbs. of water per hour. 2 Babcock & Wilcox W.I.F. Type, Single Water Tube Boilers equipped with Mechanical chain grate stokers and integral superheaters, each unit having an evaporative capacity of 7,000 lbs. of water per hour. Working pressure of all boilers—160 lb. per sq. in gauge Normal final Steam Temperature 550°F.

It is proposed later to replace the existing boilers by larger units under a working pressure of 250 lbs. per square inch, and a final steam temperature of 700°F, for which conditions the new steam Turbine plant has been designed.

The Chain grate stokers are driven by a Luth & Rosen combined electric motor and reduction gear with a reduction of approximately 25 to 1. The Boiler feed water pumps comprise:— 2 Centrifugal Feed Pumps direct coupled with electric motors and capable of delivering 133 G.P.M. against a head of 395 feet at 1,500 r.p.m. with 2 Inter-coupled Duplex stand-bye steam pumps capable of maintaining the water supply in the event of electrical failure.

The feed water is supplied by pump or by gravity, from the Low Level Service Reservoir into a common distributing tank near the boiler house and from which it can be drawn direct by the feed pumps or it can be passed to the hotwell as make up to the turbine condensate.

COAL PRODUCTION. In normal times coal is produced from two deep mines and four Open cast Mines. The former are equipped to produce the normal demand of the Colliery, the Open casts being regarded more as an insurance and safeguard against any involuntary stoppage of production.

NORTH MINE. This mine is at present closed down; the plant has been withdrawn and the workings have been allowed to flood. It can, however, be put into commission when required either by re-opening the main incline or by entering the lower workings from one of the opencasts in the same seam.

The following brief description of the mine as it operated may be included as a matter of interest.

The main incline of the mine is approximately one mile long, while the greatest vertical depth is about 800 feet. The total length of open roads and ways is 4 miles.

The thickness of the seam is up to 40 feet and the normal output of the mine 25,000 tons per month.

PUMPING. Water from all sources was handled by 5 electrically driven four stage centrifugal pumps, each directly connected with a 130 H.P. Motor, and having a capacity of 500 gallons per minute against a head of 500 feet.

VENTILATION was effected by a 94" Double Inlet Reversible Type Sirrocco Fan, driven by a 225 H.P. electric motor and exhausting approximately 150,000 cubic feet per minute at a Water Gauge of 2 1/4 inches.

This fan is still in position and will resume operation as before when  the mine is re-opened.

STOWAGE. Hydraulic sand stowage was carried out by gravity from surface bunkers in the manner described later.

4. HAULAGE. The haulage up the main incline to the pit top is of the double drum type driven by a 75 H.P. steam engine for a rope speed of 7 m.p.h. Equipment is on hand for the conversion of this haulage to electric drive. Auxiliary haulage underground was performed by 1-50 H.P. and 2-10 H.P. double drum haulages and 2-6 ton electric storage battery locomotives.

EAST MINE. The mines goes to a vertical depth of 520 feet below the ground level and the total length of underground roads and ways under maintenance is about 12 miles. The length of the main dip roadway is 2,750 feet and the average gradient is about 1 in 4.5 The thickness of the seam averages about 24 feet and the rated output is 25,000 tons per month per shift.

Apart from secondary stowage places and a little development work the coal winning is concentrated in two districts each containing a panel of coal measuring about 1,300 feet long by 200 feet wide by 24 feet thick from which the coal is extracted on the longwall principle. The length of the longwall face is the width of the coal panel and the longwalls are worked in pairs one of which is termed the advance longwall. When one of the pair is being worked the other is being stowed and so the working takes place alternately on the two faces. In the event of an emergency of any kind occurring in one district, coal winning can proceed in the other or under normal circumstances both can be worked at the same time should demand be sufficiently large.

At the present time coal extraction has just been completed to the boundary in the first lift of No. 1 district and extraction in the second lift has just commenced.

VENTILATION. This is effected by means of a 56" dia: Sirrocco Fan driven by a 150 H.P. electric motor. The duty of the fan is 100,000 cubic feet of air per minute at a water gauge of 1% inches.

The mine is divided into districts and each district comprises one section of the ventilation system; it can be controlled independently of the others and in the event of an emergency, any one district can be isolated without affecting the others.

PUMPING. To deal with ordinary mine water and water from sand stowage, two of the Colliery standard electrically driven centrifugal pumps are installed and work in conjunction with two 8" 150 H.P. gravel pumps which handle slimes and secondary stowage material in two stages at lower levels. Each standard pump has a capacity of 500 gallons per minute against a head of 500 feet, all exposed parts being, as far as possible, proof against the acid content of the water.

Ordinary mine water and effluent from stowage barricades gravitate by way of bricked lonkangs to a large brick lined sump at the lowest level of the mine. From this sump the slimes are lifted by the first gravel pump to a settling sump situated at four levels higher up, the vertical lift being about 80 feet.

At the bottom of this sump on the dip side, are fitted spigots from which the settled slimes are tapped off and lead through launders and pipes to specially arranged workings where the slimes are used as secondary stowage in a manner similar to that adopted for primary stowage. The second 8" gravel pump lifts the remainder of the slimes to another settling sump four levels higher up and the same tapping off and secondary stowage is carried out in a manner similar to that effected in the lower district. The comparatively clear water from which most of the slimes have settled out is then lifted to the surface by the standard pumps, one of which is ample to meet requirements and the other serves as a standby. To one of these pumps has recently been fitted a Michell thrust which it is hoped will lengthen the life of the pump considerably.

SCREENING. The Screening Plant is of modern design and construction, and embodies rotary waggon tipplers, jigging screens of the ring plate type and belt conveyors. The Screened coal passes over the screens, down adjustable chutes and is loaded direct into the railway waggons where an inspector examines the coal and removes any foreign matter that has escaped previous inspection. The small coal goes through the screens and is collected by a belt conveyor which delivers it into the railway waggons on

5. another line. Mine timber is elevated to pit top level by a reversible creeper, the empty timber waggons being returned to the timber yard by the reversal of the creeper chain.

HAULAGE. The main haulage is of the endless type and extends from the bottom of the main incline to the pit top. It is driven by a 75 H.P.electric motor and is fed by several auxiliary haulages which work in the various levels or roads which lead to the coal panels at present being worked.

OPENCAST Nos. 3 & 4. Owing to a fault rendering difficult the working of a part of the East Mine seam through the main East Mine entry, the faulted coal is being developed from the surface by means of two pairs of headings the inner one of each pair being 300 feet apart. This forms a long wall of that length which is laid out to produce 250 tons of coal daily by machine methods.

As in all instances of underground production at Batu Arang, this will entail the replacement of 250 tons of coal by approximately 250 yards of stowage material and at O.C. 4 a sand bunker has been constructed which will serve the requirements of the longwall in that district.

At O.C. 3 which is really a continuation of this opencast, the stowage material in the form of overburden is sluiced from above coal which is later to be won by Opencast methods, and flushed directly underground, the solid material being retained within the area evacuated of coal during the previous day or so by hessian lined barricades running parallel with the coal face, the effluent passing through settling areas at intervals along its one mile travel to the main East Mine Pumps.

In order to augment the overburden and to render it more suitable for stowage, a sand bunker is at present being constructed in the sluicing area and sand will be supplied to the bunker by means of a branch railway line, for mixing with the sluiced material as and when required.

The haulage in connection with these two opencasts is done by three electrically operated double drum machines, 2 of 25 H.P. and 1 of 10 H.P. and one similarly operated endless haulage of 35 H.P.

These workings are not in operation at present but are so conditioned that they can be put into commission at a moment's notice.

OPENCAST No. 7. The Development work in the form of shale stripping to uncover the coal was done by an electric shovel in conjunction with an electrically operated endless haulage. The shovel has a bucket capacity of 1 1/4 cubic yards, a maximum digging radius of 26 feet and the total horse-power of the motors is 95. The endless haulage serving the 3,000 feet of track was driven by a 35 H.P. electric motor.

The skips used were side tipping both ways and have a capacity of 1-1/3 cubic yards. The length of the cut varied from 1000 feet in the earlier stages of development to 2,500 feet as the work proceeded towards completion.

The capacity of the shovel is approximately 30 cubic yards per hour of shale shattered by explosives in advance. The explosives used then and now are of orthodox type but the adoption of liquid oxygen, carbon dioxide and other more modern types are under consideration and a plant for their manufacture will probably be installed.

This opencast forms a good illustration of opencast mining operations and shews very clearly the inclination and thickness of the seam and the extent to which it can" be worked by opencast methods.

The limiting factor in this respect is, of course, the relation between the thickness of the coal and that of the shale and overburden above it and when the economical limit of extraction has been reached the opencast ceases to exist as such and a mine commences. Inclined roads are driven into the coal face and further extraction is on the underground principle.

The coal winning programme now in operation is well advanced and in part of the Southern section it has been completed. The thickness of the coal seam is about 30 feet and the method of extraction is on the bench principle. Three benches were worked in the width of the face and the maximum height

6. of each was about 12 feet and each was served by the haulage system. In order to ensure efficient working and to obtain the maximum percentage of lump coal each bench was worked on the bord face principle which ensured that the maximum amount of coal could be won with the minimum amount of handling. To further reduce handling and to simplify winning, the coal is loosened by explosives in advance.

Development of the coal exposed in the Northern Section proceeds and when extraction has been completed in the Southern Section coal winning operations will be commenced and a similar system of extraction will be adopted, but for various reasons in this case, the coal will be worked from the point of shale contact towards the outcrop instead of the opposite way which is the more usual method.

HAULAGE. The main haulage which is of the endless type is driven by a 35 H.P. motor and conveys all coal, shale and spoil from the mine to the loading or dumping point. The main incline has an average slope of 1 in 4 and is about 600 feet in length. At the bottom of the incline the haulage turns at almost right angles to serve the length of the Southern section of the Opencast at present being worked. A 20 H.P. auxiliary endless haulage is situated near the foot of the main incline and serves the shale and coal operations that are being carried out at the block at the extreme end of the Southern section. Haulage track is being laid to serve the coal area in the Northern development and when operations commence the main haulage will be disconnected from the Southern section and coupled up to the North end.

All seepage and catchment water is drained to a sump situated in the South corner of the Southern section where it is lifted by two 6 inch pumps through a 10 inch main to a surface drain. The pumps are Allen's Conqueror type and each has a capacity of 700 gallons per min: against a head of 150 feet and is driven by a 52 H.P. motor.

SAND PIT. This opencast provides a considerable quantity of the sand required for hydraulic stowage and the bulk of the sand is won in the course of coal stripping. At the present time a % cubic yard Huston Shovel is operating in the sand pit which is situated to the East of the Northern section of the mine, in conjunction with a 20 H.P. haulage. The sand is conveyed to the loading gantry where it is tipped into the Company's waggons and transported by locomotive to the sand bunkers. A new sand winning area is being opened up beyond the Northern Coal section and this will be served by a 35 H.P. endless haulage circuit and will be worked by means of a 1 ¼ cu. yd. Bucyrus electric shovel.

OPENCAST No. 8. At the present time this opencast is not being worked, but is being used as a wet storage for surplus smalls. Owing chiefly to the effect of tin restriction the demand for small coal has decreased considerably and smalls are now produced in excess of requirements. The coal does not deteriorate when stored under water and as conditions improve it will be picked up and sent to the washery and despatched. Until recently in this opencast, a half cubic yard single motor electric shovel operated on coal and another machine of similar capacity but with five motors worked overburden in the North end.

It is proposed at a later date to resume stripping operations in this opencast and for this purpose it is intended to procure a 214 cubic yard shovel the design of which will be somewhat different to the other machines. The larger machine will convert its power on board from 3,300 volts A.C. to 240 volts D.C. to suit the five individual motors with which the machine is fitted.

This method and the well known Ward Leanard system of control give much greater flexibility than is possible with a straight alternating current drive, and is much more economical in power consumption. The development programme for this mine provides for a coal loading gantry and screens to span the new rail sidings, which will be operated in conjunction with the coal washery situated on the East of the opencast.

Almost all of the clay requirements of the brickworks are stripped from within the development area of this opencast, although at the present time owing to the restricted output of the brickworks very little clay is being won. The clay is loaded from a face 1,500 feet long, direct into railway waggons which are in turn locomotive hauled to the elevated track

7. above the raw materials bays at the works. The great length of face systematically worked will ensure a preliminary mix of the raw clay and so aid in obtaining 3 raw product reasonably uniform in quality.

The main entrance railway siding past this opencast is to be deviated to provide better marshalling facilities and also to make available for recovery a large quantity of coal situated under the existing track. The new track has been laid and is now partly in use but it has not yet been connected into the F.M.S.R. line at Batu Arang station. A new 60 tons weighbridge which is the property of the F.M.S. Railways has been installed and this will operate in conjunction with the new sidings.

The foundations and building for the weighbridge were supplied by the Company.

COAL WASHERY- This plant has been in commercial operation for some little time with entirely satisfactory results. The coal treated is that which, as produced, contains a higher percentage of ash than is permitted in coal despatched for sale. The capacity of the washery is 40/50 tons of raw coal per hour, according to the percentage of shale contained therein.

The coal to be washed is conveyed from the various points of production to the washery in the Company's 8-ton wagons. From the receiving bunker at the washery, the raw coal is elevated to a horizontal picking belt on which, in the course of its travel, it is subjected to a preliminary picking by hand. From this belt the coal gravitates through a crusher into a hopper, and from this into a bucket elevator from the discharge end of which the coal is delivered into a stream of water and carried along to the washer box in which the actual washing is done.

This washer box takes the form of a "U" tube closed at one end and open at the other. On the closed side pulsations are delivered to the column by means of air pressure and the coal is carried on a screen plate on the other.

The pulsations delivered to the water cause an alternate uplifting and suction effect on the coal bed as the result of which the heavy foreign materials such as shale and clay etc., sink to the bottom from where they are continuously extracted by a screw conveyor for discharge, via a bucket elevator into shale wagons below.

The light clean coal is carried over by the water on to dewatering screens which with their jigging motion convey the dewatered washed coal forward for discharge over a chute into railway wagons below. The water used for washing is in constant circulation and a conical shape settling tank is incorporated to take the slurry and sludge out of. the water and deliver it in a more or less clean condition back into the system. The make-up water is provided chiefly by the clear water sprays which are used to brighten the coal at the commencement of the dewatering screens. The clean slurry is dewatered on a special set of jigging screens and can if desired, be mixed with the washed coal or filled separately.

The whole operation is under laboratory control, samples of the raw coal, washed coal, slurry and dirt rejected being regularly collected and tested by the Chemist in charge.

The Coal testing laboratory is situated to the West of the Washery and contains modern electric equipment for making analyses of coal and the determination of its calorific value.

HYDRAULIC STOWAGE. To ensure maximum possible extraction with the minimum risk of spontaneous combustion in the workings, all coal won by underground methods is replaced by a suitable material hydraulically stowed.

Coal is won from the underground mines in 8 feet lifts by what is known as the "Long Wall method of extraction. The bottom 8 feet of the seam is taken first to a pre-arranged boundary, always working to the rise, and as the face advances the void is filled with a mixture of sand and crushed shale or other suitable materials, hydraulically stowed through pipes from the surface.

When the prearranged boundary is reached, the sand stowage, which has replaced the bottom lift of coal is used as a floor from which the second lift of 8 feet is worked, and so on, until the full thickness of the seams, which vary from 20 to 40 feet, is extracted.

8. It is the general practice in all cases other than the Longwall face worked through O.C.3, to convey the sand and crushed shale or other suitable material by rail to stowage bunkers on the surface, each with a capacity of from 500 to 1,000 cubic yards, and from which the sand is washed into a mixing chamber by hydraulic jets and from there through pipes to the various points to be stowed.

The pipes which are connected by flanges, and are either 5" or 7" in diameter, convey the solids suspended in water to the areas behind the Long Wall from which coal has been removed during the previous day or so, and around which a prop and timber frame has been arranged to take a lining of jute hessian. The hessian is of a suitable texture to retain the solid material, more or less colloidal slime excepted, while the water is released to flow through a settling area to the main pumps which returned it to the surface for further use.

The practice of hydraulic stowage, while expensive in application, not only ensures the extraction of the maximum possible percentage of the total coal in the seams, but also minimises the incidence of spontaneous combustion in the workings by taking up the weight of the roof, which, in mines employing methods other than longwall and hydraulic (or solid) stowage would be carried by pillars of coal with resultant crush, and, in our case, heating and eventual combustion.

Although at present, as a result of the contraction of sales by more than half, we are drawing the whole of our stowage material from stripping operations at Batu Arang; in the past we have drawn anything up to five trains per day, each of 22 x 8 cubic yard waggons, from the Company's sand pits at Pengkalen Kundang. These sand pits are equipped to produce up to 1,200 yards of material per day, which, after being passed over tables to extract the tin content, is loaded by gravity into railway waggons.

RESCUE STATION. The station is equipped with all the necessary apparatus for rescue work, including gas masks, oxygen equipment and general first aid requirements.

Owing to the concentration of underground operations in the one mine, most of the rescue apparatus has been taken to the office at the pit top where regular practice in its use is carried out under the supervision of qualified Europeans.

In connection with first aid work regular instruction is given to the miners by the Resident Medical Officer.

WORKSHOPS. These comprise, Fitting and Machine shops, Smith and Plate shops, Foundry, Woodworkers shop, Electricians shop and Locomotive shop.

The various departments contain suitable and sufficient equipment to meet all the maintenance requirements of the property. The Foundry has recently been extended and can produce all requirements of bronze and iron castings, the latter to a weight of 25 cwts.

The Locomotive rolling stock comprises:— 4-18 ton Hunslet, side tank locomotives 12" x 18", four wheels coupled. 2-28 ton Manning Wardle side tank locomotives, six wheels coupled, 13" x 20", superheated and fitted with lighting turbo generator. 1-28 ton Manning Wardle, side tank locomotive, six wheels coupled, 13" x 20", without superheater and lighting unit. Waggon Rolling Stock totals about 275, made up of Low and High-sides, Covered Waggons and Timber bogies.

STORES. The Colliery stores and spare parts are housed in three large brick buildings while an area between is utilised as a stock yard for rails, pipes, arching steelwork and other such material that can be exposed to the weather.

WATER SUPPLY. In laying out the new supply, the requirements were based upon 700,000 gallons per day, made up of 540,000 gallons for power and industrial purposes, and 160,000 gallons for domestic purposes# though the whole layout is sufficiently flexible to permit of a material increase if future developments should call for this.

9.The catchment area is in the Rantau Panjang Forest Reserve and comprises, including the area of 25.5 acres innundated, some 456 acres. The impounding reservoir has a storage capacity of 85 million gallons, a length of about 3/4th of a mile and a depth of 26 feet.

The reservoir is formed by the construction of a puddled clay core earth dam across a ravine 550 feet wide. The dam of this length is 29 feet high, 180 feet wide at the base tapering to 10 feet at the top, the slope of the sides being 3 to 1. The earth materials used in construction were 4,000 cubic yards of clay for the core, 12,000 cubic yards of selected material for filling next to the core and 16,000 cubic yards of ordinary filling on the slopes.

Three 4 feet x 4 feet brick and concrete culverts, side by side, pass through the dam, being closed at the upstream end by 3 feet x 4 feet steel penstocks, operated in the usual manner from a bridge on the left bank, 3 feet above top water level.

The spillway, 730 feet long by 60 feet wide, has been cut from the hillside at the left end of the dam. The overflow depth is 2' 3" for a maximum flood of 40,000 gallons per minute which represents 6 inches of rainfall over the whole catchment in 12 hours. The first 330 feet of the spillway is level, the remaining 400 feet being divided into 8 grades of 1 in 70, separated by drops of 3 feet over 3 concrete steps.

The Pumping Main is 5,720 feet long, with "Victaulic" joints throughout. The first 820 feet, being of 12" steel tube with a floating arm outlet, passes through the concrete roof of the culvert to a single stage centrifugal pump, directly connected with a 52 H.P. motor, situated at such an elevation that it is supplied by gravitation unless the water level in the reservoir falls below half depth. On the delivery side of the pump, the pipe is reduced to 8" and continues of this size over the 4,900 feet to the Low Level Service Reservoir into which it discharges 850 gallons per minute, against a total head of 180 feet, of which 79 feet is static. The usual dry well and vertical pump arrangement was dispensed with owing to the advisability of adopting one of the colliery standard horizontal pumps.

The Low Level Service Reservoir is an open, mass concrete, tank 120 feet in diameter by 12 feet deep, to hold 675,000 gallons of water at a depth of 10 feet. The tank is divided into two compartments, so that it may be used as a settling tank. With the main pump operating at its rated capacity, the tank can be filled in 13y2 hours. Each compartment is provided with a 12" floating arm outlet, while the Western compartment is also provided with a 4" floating arm outlet from which the water gravitates to a single stage centrifugal pump directly connected with a 10 H.P. electric motor, situated at a distance of about 400 feet.

This pump delivers to the High Level Reservoir 120 gallons per minute through 1,300 feet of 4" main; two 5 feet Jewell Filters being situated about half way. The total head against this pump, including the resistence of the filters, is 180 feet, of which 134 feet is static. The capacity of the pump is exactly that of the two filters, namely, 7,200 gallons per hour.

The High Level Service Reservoir is a covered mass concrete tank 40 feet in diameter, by 10 feet deep, to hold 64,000 gallons of water at a depth of 8 feet. The elevation of this tank will make possible a gravity supply of filtered water to any point on the property, a break pressure valve at 100 feet below top water level being provided to reduce the strain upon the fittings below that level. The lower levels will eventually be served by a main from the Low Level Service Reservoir to the Power House, a separate battery of four 6 feet diameter pressure filters being provided for this purpose. The completion of this work will make possible a piped supply to all principal consuming points and the installation of waterborne sewage.

SUBSIDIARY UNDERTAKINGS.

BRICKWORKS. Owing to the depressed state of the building trade, the demand for bricks during the last year was insufficient to absorb the production of our works, and with the accumulation of sufficient stocks to take care of the likely demand for at least twelve months, it was decided to cease production of our standard engineering and building bricks, in pursuance of which policy the large continuous kiln was allowed to cool off. The downdraft kiln, however, remains in use in order to meet the demand for firebricks and any other specials of which sufficient stocks are not available.

10. The following describes briefly the normal operation of the works.

The raw materials comprising plastic clays, sandyloam and weathered shale used in the manufacture of "Malacol” products are delivered to the storage shed by rail from the clay pit and other workings. The shale which is sometimes obtained from the central crushing plant where stowage material is the primary product, is further crushed by high speed rolls otherwise it is obtained direct from the shale dump. The fine material is elevated to an overhead rotary screen and bunker and the oversize is returned to a 7 feet diameter dry pan for further grinding. The clay and loam storage has a capacity of 500 cubic yards and is sufficient for 4 days requirements. The proportioning is effected by compartment tubs which when filled, give the required quantity of each material. The full tubs gravitate past the loading bays to a large capacity two shaft horizontal mixer driven by a 50 H.P. motor; the empty tubs being conveyed by means of a 5 H.P. endless haulage, back to the head of the loading bays.

The proportioned material is delivered to the double shaft mixer at the rate of about 50 tubs per hour. The mixed material is then elevated by means of an 18" belt conveyor, 85 feet centres, to the top rolls of the brick machine.

In this machine which is driven by 150 H.P. motor, the material passes through three sets of closely set rolls and a double shaft mixer, and finally through a pug mill and die from which it exudes at the rate of 26 feet per minute in the form of a slab 9%" wide x 4%" thick.

The slab is cut to lengths of about 2' 10" and moved on to the table where each is wirecut by one movement into 10 bricks. The wirecuts are placed on stillages which are conveyed by a lifting Auto Truck to the drying floors where the bricks remain for about 48 hours before being put into the kiln.

The bricks for pressing are passed down an oil lubricated inclined table to the presses which have a combined capacity of 3,000 per hour, from where they are taken to the drying floors by Lifting Trucks.

The drying floors are heated by steam supplied from the main boiler house, and have an area of 20,000 sq. ft. and a capacity of about 50,000 bricks per day.

The dried bricks are lifted from the floors and set in a 14 chamber improved Hoffman Type Kiln, of which each chamber is 21 feet long, by 16 feet wide by 9 feet high, with a capacity of 20,000 bricks. Malayan coal is used for firing and is fed by gravity from the top of the kiln. The travel is between 30 and 35 chambers per month, and the rated capacity is 750,000 bricks monthly. In addition to ordinary common building brick, either wirecut or pressed, this kiln is used for firing perforated and cavity bricks and hollow building blocks. The draft is created by a brick stack 50 feet high or by a 50" Sirrocco fan directly coupled to a 30 H.P. motor, and connected to the chimney. Designs have been completed for a second kiln of a similar type, but embodying a number of improvements, and of 22 chambers capacity.

For other goods, such as roofing tiles, glazed and sand faced brick and glazed sanitary pipes, a down draft kiln is placed on the South West corner of the works. This kiln is 40 feet long by 16 feet wide by 9 feet high and has a capacity of approximately 5,760 cubic feet. Firing is effected by Malayan coal fed to twelve fires, six on each side and draft is natural by multiple chimneys. When this particular type of kiln has proved satisfactory for our requirements and when trade conditions improve further units will be added as the capacity of the works is built up.

The Tile-making plant is situated at the North West corner of works and is laid out so that it can be extended to obtain increased output and to include a pipe making department. The present plant is of the nature of a pilot plant and only the minimum amount of machinery has been installed although the possible output is of the order of 150,000 interlocking roofing tiles per month. The raw materials which are similar to those used for brickmaking are spread on a steam heated drying floor of 1550 square feet area, where they are thoroughly dried prior to grinding.

11. The brickworks grinding plant is available for the title plant and the ground materials are transported in skips which gravitate to a hopper into which the contents are tipped. This hopper forms the boot of a bucket belt-elevator which conveys the materials to an overhead four compartment storage bunker. Before reaching the bunker the materials pass over a plate screen and then to any one of the compartments by means of a spiral conveyor. The trough of the conveyor is fitted with doors which can be opened in order to deliver the materials to the compartment desired and each compartment will contain its particular class of ground material. The bunker compartment bottoms are roughly conical in shape and are fitted with slide valves which are opened to admit the materials to batching tubs which receive the materials in the desired proportions.

The batching tubs convey the materials to the wet grinding pan into which they are placed after receiving a preliminary mix.

The pan which is by Johnstone & Co., is 9 ft. in dia: and is belt driven by a 24 H.P. motor. After being thoroughly ground and brought to the desired degree of plasticity by the addition of water, the material is extracted from the pan by means of a shovel attachment and conveyed to the souring floor by flat topped trucks. After being allowed to sour for at least a week the clay is taken to a 45 H.P. pugmill where it is further rolled and mixed and from which it is exuded in the form of a column about 9" x 5 1/2". As it exudes it is wire cut into five slabs about 12" in length and 1" in thickness. From the cutting table the slabs are passed along table trays where they are oiled and prepared for feeding to the tile press.

Should it be found beneficial a further souring or tempering process will be included between the cutting table and the tile press.

The tile press which is by John Whithead & Co., is belt driven by a 10 H.P. motor and has an output of 500 tiles per hour.

A feature of the press is the double pressure action effected by means of three cams one of which lifts the die between the two presses, the object of the double press is to allow air to escape before the final pressure is applied.

The lower die of the machine comprises a revolving drum fitted with five dies and the drum revolves one fifth of a revolution at each movement and coincides with the upper die which moves only in the vertical direction.

The oiled clay slabs are fed to the press by hand and are taken into position by the revolving drum.

The pressed tile comes out at the other side of the press and is collected on a wooden pallet as it drops from the lower die.

Between the process of collecting the tile and feeding the slab, the lower die is cleaned and oiled. The tiles are then trimmed by hand and conveyed on barrows to the drying racks positioned over the main steam heated floors where they remain for about four days before being set in the kiln for firing. When the future of the tile is assured further mechanical equipment will be added and handling will be reduced to a minimum.

CERAMIC RESEARCH. Adjacent to the Superintendent's office is a laboratory which contains the latest equipment for examining and testing raw materials and finished goods and the Ceramic Chemist devotes his time to the improvement and development of the various products.

For small commercial scale tests of various combinations of materials in goods of various kinds, a small kiln to the South of the laboratory building has been provided. In connection with the laboratory work there is a small experimental pottery department which has achieved some quite interesting results.

PLYWOOD WORKS. This factory has been in commission for about a year and half and as the result of the encouraging reception given to "Malaply" products the plant has been extended and the output increased by about 50%. All timber used is obtained from the vicinity of the factory the output of which is about 20,000 square feet of plywood, or 60,000 square feet of veneer per day.

12. This takes the form of rubber chests, pineapple cases, building panels for ceilings, walls and doors etc., in which latter connection, precautions are taken during manufacture to render the product impervious to the effect of moisture and the attack of insects.

The logs arrive from the forest by rail in lengths of about 5 feet and diameters of up to 40 inches, and are either discharged into the storage pond or taken to the steaming vats. From the vats they are conveyed by overhead runways to the lathes where they are peeled into veneers from 1 to 2 millimetres thick by 42 to 54 inches wide. The veneers then pass along a slat conveyor to the clipper where they are cut into lengths of about 44 inches after which, they are placed on drier cars and put through the progressive drier. In this drier an air flow of about 40,000 cubic feet per minute is produced by a 48" Centrifugal fan driven by a 45 H.P. motor, heating being effected by a bank of steam tubes. The moist air is exhausted by a second fan at the other end of the drier.

The dried veneers are taken to the glue spreading machines and then to the hydraulic press. About 30 sheets of plywood are pressed at a time, after which the plywood is returned to the drier for final drying.

Split or undersize veneers are put through a taping machine which joins them up and makes them equal in quality to an unbroken veneer.

From the drier the finished plywood is taken on the trolly tracks and delivered to the edging machine or guillotine where it is trimmed and cut to the required size, after which it passes to the sanding machines to receive the desired finish. The plywood is then ready for packing, or fitting to suit requirements.

The battens department takes its wood supply from cores from the peeling lathes or direct from the logs.

The logs and cores are broken down in the Sawmill and passed in the form of planks to the edging machine which produces the batten stock 1" x 1" x 5 feet. The stock then goes to the thicknessing machines where it is sized to %" square after which it is loaded on to ball bearing trucks and passed through the drier. The thoroughly dried stock is then cut into battens as required and packed for despatch.

SAWMILL. In addition to supplying planks and batten stock for the Plywood Department the Sawmill provides the general sawn timber requirements of the Colliery.

The mill which is electrically operated has a capacity of about 5,000 Board feet per day and comprises the following machinery.

1-54" Rack-feed Circular Saw Bench with 32 ft. carriage for breaking down. 1-30" Vertical Frame Saw for planks etc. 1-36" Saw Bench for edging and small dimensions. 1-14" Circular saw edging machine. 2 Thicknessing machines. 1 Four cutter planing machine.

With a view to extending its sawmill activities the Company has recently acquired a complete sawmill and logging plant capable of turning out 50,000 Board feet per day. The site has been prepared and details of the mill layout are being considered and negotiations are proceeding with Government in connection with forest areas for logging.

WOOD DISTILLATION WORKS. This plant is situated due North  of the Plywood Works and due East of the Sawmill site and it is designed to work in conjunction with these works. The plant has had a satisfactory trial run and operations are suspended pending complete examination of the various products.

13. The capacity of the plant is about 30 tons of air dried timber per day and the timber used for distillation will be obtained from waste from the Plywood Factory, Sawmill and Workshops. The plant under normal conditions will operate continuously and the main products will be charcoal, grey acetate of lime, wood alcohol and wood preservative.

The wood after sufficient seasoning in the yard sheds is filled into special cars dimensioned 6' x 10' x 4'-6", four of which are run into each retort. The retorts are then closed and subjected to heat.

The tar and liquor separated out in the retort condensers is led to the settling vats which are of sufficient capacity to hold three days supply. From the crude pyroligneous acid vat, the liquor is led to the acid stills and the condensate there from to the clear acid storage tank. The clear acid is then neutralised with lime and the neutral liquor is pumped to the neutral liquor vat, from which the liquor is led to the Lime Lee Stills. The condensate from the Lime Lee still condensers is led to the crude alcohol storage tank and from there to the rectifying still and thence to the refined alcohol storage tank. The residue in the Lime Lee Stills is led to the seeding pans from which, when most of the water has been evaporated, the acetate of lime is filled out on to the drying floor.

The residue of the acid stills is led to the tar storage tanks and thence to the tar still, the vapours from which are led to the acid condensers.

All stills, condensers, storage and settling vat£ are arranged at suitable levels whereby gravitational flow is made use of to the maximum extent possible. One of the retorts is so connected that it can be isolated for the purpose of carrying out experiments on distillation of coal, rubber and other products.

After distillation of the wood has proceeded for about 36 hours the charcoal is removed by means of a suitable mechanical haulage, water quenched and run into the coolers, where it remains for about 24 hours. The charcoal is then taken to the store where it is graded and made ready for sale.

The stills are heated by means of steam coils and the acetate drying floors by the gases from the retorts and from the steam boiler. All gases are led through flues to a common self supporting steel chimney 6' diameter and 100' high which is capable of producing draft for any extension to the plant.

A laboratory is incorporated in the Superintendent's office where samples of the various products are examined by the Chemist.

CEMENT MANUFACTURE. Very complete investigations have been carried out on the material available for the manufacture of cement, and it is hoped that it is only a matter of time when the Company will feel justified in adding this to its activities.

AGRICULTURE. The Company being anxious to utilise the agricultural possibilities of at least part of its leases have been experimenting with different products, an area of 17 acres being utilised for this purposes. Results to date have not been efficiently conclusive to justify any definite recommendation.

ADMINISTRATION, The main office building houses the Mines Superintendent and officials of the various departments, with the exception of the Under Managers who have their own offices at the North and East Mines and the Opencast Superintendent, who has a more centrally situated office. The Brickworks Superintendent and Chemist are housed at the Brickworks as is also the Plywood Superintendent at the Plywood Works.

TELEPHONE SYSTEM There is a telephone system with just under 50 connections which link up every important point on the property both on the surface and underground. The Colliery office is connected with the Head Office in Kuala Lumpur by a private line.

HOSPITAL. There is a Hospital and a dispensary in charge of a resident medical officer where all persons employed on the property receive treatment free of charge, although it can be said that the property is remarkably healthy and free from disease.

14. BUILDINGS. The European members of the staff are accommodated  in bungalows on the slopes of the hill facing East and overlooking the main  operations.

The labour force is housed in buildings of various types and it is hoped to complete the conversion from temporary and semipermanent buildings at an early date.

A recent addition in this connection is the Tamil lines at the East side of Opencast No. 8. They are constructed of bricks on concrete foundations and have a Salonit roof. A jack roof, and perforated ventilation bricks provide for the necessary ventilation. There are 20 houses in each of the two rows and each house has its own kitchen, placed at a suitable distance in front. The total number of occupants is about 140.

Between the two lines are the bathrooms and lavatories suitably arranged to accommodate all users. A trough flushing system runs throughout the length of the lavatories and discharges into a septic tank at the Southern end; water cisterns are placed on brick piers at the North end.

The capacity of the system and septic tanks is sufficient to provide for extension of the lines.

With the new water supply completed, installation of water borne sewage for all buildings is being commenced.

South of the Main office is the village which comprises 20 shop houses of two story brick construction and a number of attap shops. These latter await the erection of a market building, which is about to be commenced.

A little further to the South is the village green, the centre court of Batu Arang athletics which are comprehensive. Overlooking this is the Asiatic Sports Club building which is managed by an Asiatic Committee with as ex-officio President the Mines Superintendent, and as Sports Organiser, one of the European Colliery Officials.

Alongside the village green is the open air Cinema, where the resident population are the guests of the Company on Sunday evenings. The Company's private road which is 2 ¾ miles long, connects with the Government Road from Rawang to Batang Berjuntai, at about the 26th mile.

PERSONNEL, DIRECTORS. H.H. Robbins, Esq., (Chairman) (on leave). W. H. Martin, Esq., (Deputy Chairman). A. J. Kelman, Esq., F. Cunningham, Esq., R. C Russell, Esq., J. Drysdale, Esq., B.Sc. (Alternate for H. H. Robbins). General Managers. Messrs. J. A. Russell & Co., Kuala Lumpur. Consulting Electrical Engineers. Messrs. Sparks & Partners, London. Consulting Colliery Engineer. E. 0. Forster Brown Esq., M.I.C.E., M.I.M.E., London. Consulting Fuel Technologist. Clarence A. Seyler, Esq., B.Sc., F.I.C., Swansea. Consulting Clay Technologist. Messrs. A. B. Searle & Staff, Chalbury, Oxon.

COLLIERY STAFF. Acting Superintendent - - - F. Bellamy, Esq., Chief Engineer - - - - D. Tooms, Esq., Mechanical Engineer (on leave) - F. Gradon, Esq., Mechanical Engineer - - - J. A. Porteous, Esq., Electrical Engineer - W. B. Joiner, Esq., Civil Engineer & Surveyor - - D. L. Lawrence, Esq., „ „ Appr. Asst. & Traffic Supt. - K. Jorgensen, Esq., Draughtsman (on leave) - - J. J. Gibson, Esq., Under Managers - - - - R. Scott, Esq., A. Knight, Esq., Opencast Superintendent (acting) - B. Harold, Esq., Brickworks Supt. and Chemist - - E. G. de Muschamp, Esq., Wood Distillation Superintendent - E. G. de Muschamp, Esq., Plywood Works Superintendent - - E. G. Spall, Esq., Forest Engineer - - - - E. L. Jorgensen, Esq., Works Accountant & Stores Supt. - J. H. Tubb, Esq., Resident Medical Officer - • - Dr. Kirpal Singh Sodhi, M.B.B.S.