PASSENGER LIFTS (Drawing No. 18).

The construction of these is in some respects much the same as described, p. 20.

A well is sunk in the centre of the lift shaft, rather deeper than the height to be lifted. When constructed in the London district-where gravel and sand are usually met with near the surface the water is shut out by sinking cast-iron cylinders; these should be 3 feet in diameter, and in, say, 6 feet lengths, flanged together and well bolted. The first cylinder has a cutting edge at the bottom, and when the clay is reached, they are driven from 2 to 3 feet into same, to form a joint, and prevent the water rising under the cylinder. The rest of the well may be in brickwork, 4 or 9 inches thick, and either laid dry or in cement; this must depend upon the nature of the ground. Great care must be taken to keep the well vertical.

The cylinders are suspended in the well, and in these the rams work; the length or stroke is equal to the height to be raised. The ram works through a bored head fitted with gland and leather collar.

The cage is attached to the top of ram, and is made of wrought iron, well framed together. The top is 1-inch wroughtiron plate; the floor oak, and the sides pine.

Cast-iron planed guides are fixed on stone templates built in the walls at each side of the lift hole.

To the top of the cage are attached two wings, to which the counter-balance chains are fixed on either side. These chains work in grooves, and pass over two wheels fixed on the side walls, and so to the counter-balances, which work in iron guide bars fixed each side of the grooves in the wall on either side of the lift hole.

The valve gear to work the lifts is fixed below, and selfacting stopping gear is also provided to prevent accident. Every possible provision is made to ensure perfect safety.

SHORT-STROKE RAM LIFTS (Drawing No. 33)

Are made in much the same way as the above, except that the cage is dispensed with, and a table or platform is attached to the head of ram. Two iron guide bars are fixed at the

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sides, and rubbing guides to the table. It is advisable in most cases to fix counter-balances, to take the weight of the table and part of ram. The wells, cylinders, etc., are as before.

The valve arrangement is similar to the other lifts, but smaller as to pipes, etc. Self-acting stopping gear is provided to stop the lift at the highest and lowest points.

This class of lift is very suitable for banks or any place where valuables have to be stored. The entrance in this case to the safe or strong room is by the lift only; the top plate of table is made of wrought iron, and fits into an iron frame at the top floor, similar to a safe door; a patent lock throwing out eight bolts into this iron frame, is fitted to the under side of the plate; the pressure is left on the ram all night, the gear for regulating this being shut up in a recess, and fitted with an iron safe door and patent locks.

Where heavy safes containing documents for daily or hourly reference are required, the safes are fitted with wheels and run on rails on top of the lift table; rails are also laid in the vault or strong room, by which means the safe is run off into an inner strong room if required; the lift then rises, and brings down any others, and the books, specie, etc.

SHORT-STROKE RAM LIFT (Drawing No. 34).

The general details of this lift as to ram, cylinder, etc., is the same as the last named. The guides are fixed at the back, to enable the table to rise above the level of floor or street at the top, so as to allow casks or other goods to be rolled off at the level of carts, etc.

A lift of this kind is very suitable for a brewery or wine cellar, where the table rises to the level of the public way, and where no fixings for guides can be obtained at the front side of the lift at this level.

There are many other modifications of this kind of lift suitable to special requirements, but as they are seldom used, further detail is not necessary.

The great advantages of lifts (as Drawings Nos. 33 and 34) are perfect safety, noiseless action, and total freedom from vibration; the speed is also under absolute control, and they cannot be overloaded. The wear and tear is very small, even when

the work is constant. The cost of water is not a large item, and is hardly worth taking into account, considering the saving of labour, etc.

All the parts are simple and free from complication, and there is nothing likely to get out of order.

The friction of "ram lifts" is small, especially when the leather collars are well fitted, it does not exceed 5 per cent. Packed glands of any kind are to be avoided, friction is much increased by their use. The lubricant used should be good sperm or mineral oil, and the ram kept very clean; vegetable or lard oil should never be used.

SHORT-STROKE CYLINDER LIFTS (Drawing No. 35).

These lifts are very suitable for raising goods, coals, luggage, food, and other light goods.

The most simple plan of construction is an open top vertical cylinder fitted with piston, having a rack attached to the top side; this rack gears into an iron pinion, and by means of a train of wheels, rotary motion is given to a drum, and the requisite amount of rope or chain is coiled. The stroke of the cylinder and the number and proportion of the wheels are regulated by the height to be lifted. However carefully made, there is much friction in this class of lift, and a good margin must be allowed to ensure sufficient power and to spare to do the work.

The bucket or piston should be fitted with two leathers; hemp or metallic packing cause more friction. All the teeth of wheels should be pitched and trimmed; the back and sides of the rack should be planed, and work against a turned wheel fixed at top of cylinder to form a guide; the working pinion should be provided with shrouds turned on the edges, which also rub on the faced front edges of the rack.

Great care should be taken that all the work is perfectly true and of the best kind, otherwise much power will be lost by undue friction.

In well-constructed machinery the friction may be taken at about 25 per cent.

Short-stroke cylinders (see Drawing No. 4), with chains and movable pulleys, are also sometimes used, and especially where

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the working cylinders must be fixed horizontally. More friction takes place with this kind of gear than the one above described, but it may be materially reduced by attention to the quality of the work and proportion of the parts.

The cages are made much the same as those for highpressure lifts, except that all the parts can be much lighter. Gear rods or ropes pass up the lift hole to enable the lift to be worked from any floor.

Counter-balances are fitted to these lifts. They are made flat in shape, with planed grooves to run in two L-iron guide bars. The weight of the balances is less than the cage, to give sufficient power for the cage to fall, when empty, by its own gravity, and keep the ropes taut on the drums.

Self-acting stopping and safety gear is also provided to prevent accidents.

Wire rope is the best to use for raising the goods. In some cases two ropes are used, working upon separate drums; if one 1ope breaks, the other is able to take the load safely, and so avoid accident to the cage and its contents.

Lifts of this kind are very suitable for private houses, to carry up food from the kitchens, also coals, etc., to the various floors. The cost of water is not a large item, considering the great saving in labour and time effected. They are not liable to get out of repair, and are easily worked. The speed can be regulated, load controlled, and the attendant cannot either work the lift more rapidly or take more than the maximum weight.

PARCELS LIFT.

Drawing No. 36 shows a very useful application of Brotherhood's three-cylinder hydraulic engine to small lifts, introduced by Mr. E. B. Ellington. The engine is reversible, and carries a grooved pulley, round which is passed a rope, attached at both ends to the lift boxes, and having an adjustment for keeping the ropes taut. One box ascends while the other descends, thus effecting a great saving in time and power. The boxes can be worked by hand, by means of a second rope passed over the head sheave. A high speed can be obtained; the lifts are quite silent, and easily controlled.

BROTHERHOOD'S PATENT THREE-CYLINDER HYDRAULIC

ENGINE.

Brotherhood's three-cylinder hydraulic engine is a great improvement upon the ordinary Armstrong type of oscillating cylinders.

A really reliable hydraulic engine was much wanted, and as Mr. Brotherhood's has stood the test of several years' constant work, he is to be congratulated on his success.

The working parts consist only of the three pistons and connecting rods, one crank, and one rotating balanced valve and spindle which fits into the driver, and is turned direct from the crank pin.

There are no glands, stuffing boxes, or oscillating joints, and the wear of all the parts is taken up automatically, so that nothing has to be tightened up. The engine is made reversible if required, simply by a modification of the engine valve and the addition of a controlling valve to alter the direction of the flow of water into and out of the engine. Mr. E. B. Ellington has effected some useful improvements in these valves, by which certainty of action is secured. The working parts are all protected; the engine occupies very little space, and will work up to 200 revolutions per minute.

These engines have been adopted for working the hauling gear for the sliding caissons, and for controlling the sluices in the extension at her Majesty's Dockyard, Chatham.

LOW-PRESSURE HYDRAULIC POWER can also be employed for organ-pumping, working small engines, turning (small) lathes and other machines, and to a variety of purposes too numerous to detail here.

The author is of opinion that the application of this power is still in its infancy, and if water companies would be more liberal in their arrangements with regard to the use of water direct from the mains, engineers would turn their attention to the design of many kinds of apparatus where water power could be usefully employed, this more especially refers to machines for domestic use, and in large establishments, where saving of time and labour are so essential.

The great advantages of self-acting water power apparatus of this class are there is no necessity for a steam boiler; the