a warm glow
Steam engine still creates
a warm glow
Driving a steam traction
engine used to be one of the
best paid jobs on the farm,
but the disadvantages
included early morning starts
and few comforts as
Mike Williams discovered
when he took the wheel of
The Empress of Britain
During the golden age of agricultural steam power, which lasted for about 60 years until tractors began to take over during the First World War, traction engines were the nearest equivalent of the modern tractor.
Ploughing engines stayed on the headland and powered a winding drum with a steel cable to pull ploughs and cultivators to and fro, and portable engines were used only for driving stationary equipment. Traction engines offered more versatility, pulling heavy loads and also driving a belt pulley to operate threshing machines and other stationary equipment.
Apart from versatility, a traction engine has little in common with a modern tractor, and in terms of operator comfort and safety the gap is enormous. This was particularly evident on the cold, wet day when I drove the Empress of Britain and thought wistfully of a tractor cab with a heater, radio and suspension seat.
General purpose engine
The Empress is a general purpose traction engine. It was built in 1912 at the Burrell factory at Thetford, Norfolk, and Burrell traction engines were the finest money could buy – as any Burrell enthusiast will confirm. It weighs 9.5 tonnes, has the usual two-speed transmission, and it features the single crank compound piston layout patented by Burrell. The working pressure is 180 psi and the output is 7nhp or nominal horsepower, a measurement which bears no relationship to the DIN hp rating used for tractors.
One of the disadvantages of working with steam power is the time taken to prepare for a days work. For a big engine like The Empress it takes about two hours, which means someone has to make a 5am start to have the engine ready for work at a respectable time.
Most of the two hours is needed to light the fire and heat the water to build up the steam pressure, but when an engine is used every day it is possible to halve the time needed to get up steam by banking the fire down on the previous evening to keep the water warm over night.
Lighting the fire is not the first job in a steam engine drivers day. David Blackburn starts by using a long handled brush to clean soot from the steel flue tubes which carry heat and smoke forwards from the fire. This should be done before lighting the fire, and he also checks the grate to make sure there is no build-up of clinker which could damage the bars.
Mr Blackburn is one of the volunteers who helps maintain and drive the excellent collection of steam engines and other equipment in the Museum of East Anglian Life (MEAL), Stowmarket, Suffolk. The museum is the retirement home the 86-year-old Empress shares with a unique pair of 1879 Burrell ploughing engines plus an 1887 Ransomes, the oldest Ran-somes traction engine in the world.
Climbing on to the drivers platform or "manstand" as it is known, is a journey back through more than 80 years to a different age. The space is surprisingly small and cluttered, although it is supposed to be a working area for two people.
Driving a big traction engine on public roads was officially a two-man job. One person operates the steering while the other adjusts the regulator, changes gear, pumps water and also puts another shovel full of coal on the fire every 10 minutes or so.
Another job for the drivers assistant is operating the brakes. The principle method of stopping is using the reversing lever to apply steam power to slow or stop the engine. All traction engines, it seems, also carry a wooden block which is placed against one of the wheels as a parking brake, and some later engines including the Empress, also have a transmission brake operated with a screw action to tighten two wooden blocks against a drive shaft.
None of the brakes seems ideal for emergencies, but the 6 or 7mph top speed of a traction engine means the braking performance does not have to meet JCB Fastrac standards.
Gear changing is also distinctly old fashioned. There is no clutch, and the engine must be stationary when the gear lever moves sideways to change ratios or select neutral. Like everything else on the Burrell, the transmission is beautifully engineered, and as the mechanism is fully exposed the operator can watch the gears engage or disengage.
Small steering wheel
The small steering wheel is at the side of the manstand, presumably to leave most of the limited floor area for the other driver who has to move to the various controls and do his stoking job. At some stage in the last 86 years the removable seat for the steersman has been permanently removed, and there never was a seat for the second driver.
The steering wheel, so close to the spokes of the massive flywheel that it would give a safety inspector sleepless nights for a week, is linked to the front axle by a chain. Although it looks primitive and lacks power assistance, the steering mechanism is surprisingly light and easy to operate. The lightness is helped by the gearing, which means a lot of turns on the steering wheel for a small direction change, and Mr Blackburn points out that the solid rubber road bands attached to the wheels also help to make the steering easy to operate.
The biggest surprise is that a machine as big and heavy and outdated as the Empress can be driven with so much precision, and an experienced driver like David Blackburn can manoeuvre the 9.5 tonnes Burrell as easily and as accurately as any modern tractor.
It is easy to understand why the quiet smoothness of steam power attracts so many enthusiasts. Mr Blackburn says a well maintained classic engine like the Empress would sell for about £35,000 at auction – in spite of lacking a heater, a radio, ABS, airbags… *
Refuelling stop… Another plastic sack of household coal prepares itself for the bunker.