Wednesday, 14 September 2011
More achievements by Merryweather of Greenwich
Neil Bennett has sent us the following:
Did you know that a Rotary Internal Combustion Engine was conceived and developed in Greenwich High Road, in 1895, thirty-four years before the famous German, Felix Wankel, secured his first patent?
James Compton Merryweather, and his equally eminent engineer, Christopher Jakeman, diverted their energies from fire-fighting equipment to this intriguing project at the zenith of late-Victorian mechanical engineering enterprise.
A drawing of the Merryweather rotary engine is attached, but there isn't space here to try to explain how it works. I doubt very much whether the engine ever worked for more than a few revolutions, even assuming a prototype was actually built, because the builders did not have access to spark-plugs as we know them today, and instead proposed 'hot tube ignition' which must have been far less effective.
Interestingly, itwas not the world's first patent for a rotary internal combustion engine: three earlier ones were taken out in America alone. I have yet to discover an earlier patent for such a thing in Britain - so there's a challenge to all you googlers and researchers.
Ihe mid-late 1960s the London Fire Brigade were seeking new premises to replace their old fire station in Cannon Street. In 1956 the hovercraft had been invented, and ten or so years later, firechiefs were ambitiously contemplating a high-speed fire and rescue hovercraft for the Thames. It was even proposed that a gently sloping ramp would lead from the fire station building into the water, the vessel could be rapidly launched like an R.N.L.I. lifeboat, and would hover her way back up the ramp after each mission for servicing.
What seems to have been overlooked, however, is that when the fire-fighting water jets from the water cannons (monitors) on the vessel were at full throttle, the whole hovercraft would shoot off in the opposite direction, by Newton's Law. That is unless a huge amount of energy was expended in fuel powering highly-tuned aviation propellors, just to maintain the hovercraft on station and remain manoeuverable while it fought a fire. This was not the answer.
The firm Hovermarine had what is known as a 'sidewall' available -a vessel with the hovercraft's virtues of an air-cushion giving high travelling speed, but able to rest in the water, having a ship's rudder and ordinary diesel engines. The sidewall design of hovercraft,as opposed to the better-known amphibious type, cannot leave thewater.
In May 1967, Hovermarine and Merryweather together announced their fire-fighting and rescue vessel and there was a serious intention to build at least two of them. They would have been over 50 feet long, with Merryweather pumps and fire fighting equipment...but it never happened.
Financial issues and a fire at the Hovermarine works contributed tothe vessel never seeing the light of day. The Cannon Street firestation was replaced by Dowgate Fire Station, in the huge Mondial House building in Upper Thames Street, which is close to the river,but in its final form does not have access to the Thames bank. By about 1980, Hovermarine had indeed built four similar high-speed Fireboats for the Port of Rotterdam, but sadly by this time Merryweather and Sons had been left out of the contract and were in the throes of their move out of Greenwich.
Here is an artist's impression from 'Fire' magazine, June 1967, of what the Hovermarine/Merryweather vessel might have looked like... and what's more, I seem to remember having a clockwork toy boat looking exactlythe same - has anyone got one?
Merryweather and Sons has made the progression from a large heavy-metal manufacturing company employing hundreds of men (and a few women) between the banks of Deptford Creek and the Ashburnham Triangle, to a compact and profitable business in rural Kent. Britain's manufacturing prowess, with Merryweather on its meridian in Greenwich, has given way to the Service sector, as seems to befi tmodern times. The company's increasing range of services to corporate and municipal clients remains wedded to fire protection, as follows:-
- Servicing of fire extinguishers
- Service inspection and repairs to dry fire rising mains
- Service inspection and repairs to wet fire rising mains
- Installation of fire alarm systems
- Installation of emergency lighting systems
- Carrying out of fire risk assessments
- Carrying out of structural and passive fire protection work
- Fire training
Posted by M at 06:50