The reviews of our meetings form the backbone of the newsletter and we have had some excellent speakers since the last newsletter produced. They give us the opportunity to remember items that have slipped out of our very short term memory and give us a chance to reflect on matters of interest. I must admit that I spend a fair time searching for suitable images to add to the reviewers words and in doing so come across some very interesting items that have nothing to do with the reviews and I have included one such item later in this newsletter.
Our chairman at our highly successful Autumn Luncheon talked about the next three engineers to be have plaques on Engineers Walk namely Silvanus P.Thompson, Sir Humphry Davy and Sir Stanley Hooker giving brief biographies of their lives. In researching for suitable images for the Engineers Walk website I came across a fact that I had not noted before - Humphry Davy was the inventor of electric light. Ever since working in the early days in a drawing office with a Carbon Arc Light Copier I have felt strongly that there should be working examples in Museums of Arc Lights. The hiss and noise make them more living than most lights. Until now I had assumed that like most Electric Appliances The Arc light came about when Electric Power became available - but no it was based on battery cell power and invented in 1808/9 as shown in this illustrated item from the Engineers Walk website:
Collection of Dr. Bayla Singer
Humphry Davy demonstrates his new electric light for the members of the Royal Institution of London 1809.
Power is drawn from the banks of batteries in the basement and rapidly used up by the intense light. Electric light was then only a scientific curiosity, practical only when expense was no object.
Do visit the Engineers Walk site at http://www.engineerswalk.co.uk/
Talk by Prof Ralph Benjamin
CB, PhD, DSc, DEng, FIEE, FCGI, FREng.
9 August 2006
Having read the preliminary write up to this talk, we waited with trepidation for Ralph to begin. But his presentation was both straight forward and concise. For more than 60 years almost all of his projects were triggered by “XYZ can't be done”, given the standard assumptions and established approaches, and completed by thinking outside those assumptions.
For each of his 5 topics he first explained why there were problems. He then showed how the problems could be solved by using a different approach.
Smart Mobile Base Stations and Dumb Terminals
There are many routes between a base station and a mobile phone due to signals reflecting off buildings etc. Signals arriving at the mobile can interfere with each other, producing poor quality sound. This is countered by having complex channel-matching, diversity antennas and equalisers at both the mobile and the base station. By interleaving the transmit and receive signals at the same frequency, a training signal from the mobile unit can characterise its propagation path both to and from the base station. The burden of processing is transferred from the many sparsely used mobiles to a few intensively used pre-processors at the common base station, thus saving the complexity, bulk, weight, power consumption and cost of the mobile. Analysis shows that providing equipment for 20 simultaneous calls produces a signal to noise improvement of 100,000.
As an aside Ralph showed that the best place to site a Base Station is at a school. Using the inverse square law, the power of a transmitted signal 50m from a base station is 1,000,000 times less than the power 5 cm from a mobile phone transmitting at peak power. In order to save on battery power a mobile phone transmits at a power inversely related to the power of the signal it receives from the base station. So the nearer the mobile is to the base station then the lower the power it uses to transmit.
X-rays with CAT-scan quality, but minimal irradiation
Ralph explained that ordinary X-rays can not distinguish between absolute and relative size, depth location, thickness and density of components within a target object. He showed how a CAT-scan gets round this problem by using multiple fan beam images. Unfortunately this requires a very high dose of radiation – about 100,000 times that of a normal X-ray. It also requires expensive fast moving equipment. He showed that a moving target produced a blurred image. The patient can be asked to hold their breath for 10 seconds but not to stop their heart beat. By using a totally different way of analysing the data, Object Based 3D Imaging, Ralph showed how the radiation level could be dramatically reduced together with an enormous reduction in data processing and storage. The equipment is relatively low cost, has no moving parts and can cope with a heart beat. This method of analysing intersecting fan beam images produces a wire frame representation of the object. Computer graphics can then be used to convert the image to a more life like representation.
Finding explosives in aircraft luggage
Object Based 3D Imaging gives a much improved determination of density. It can detect a difference of about 2% between materials, sufficient to discriminate between plastic explosive and Haggis hidden in luggage. 10 stationary fan beams are arranged along the luggage security screening tunnel. The time shift of the luggage travelling between the beams is used to simulate two beams intersecting.
Seeing “invisible” buried land-mines
Land mines kill and maim indiscriminately, make vast areas inaccessible and are being laid faster than they are being cleared. Traditional methods using a plastic probe and metal detectors, are dangerous and do not work with plastic mines. Ground penetrating RADAR fails when a mine is small, plastic or flush with the surface. RASOR – Real Aperture Synthetically Organised RADAR uses an array of antennas. By using all of the transmitter to mine to receiver paths between the different antennas and allowing for the distance between the antennas on particular paths, a more accurate position of the mine can be computed. About 30 paths are required to detect a flush buried plastic mine. This technique has many applications:
Road works - buried pipes, cables, ducts
Forensics - arms, loot, buried bodies
Terrorism - through wall imaging
There is also the potential for an acoustic variant for observing heart action and a moving belt system to detect food contaminants. But the most interesting is the detection of breast cancer.
Detecting “undetectable” tumours
Breast tumours have poor X-ray contrast, 20% are missed, and more than 20% false alarms are produced. Using 10GHz RASOR tumours as small as 2mm are detectable. The technique can also see places, such as towards the arm pits, that are difficult for X-ray mammograms. Screening time is about 2 minutes, much more comfortable for the patient and once in mass production it could be cheaper.
Ralph’s last slide showed how difficult it is to get innovative solutions to market. The mobile phone developments have been sold to Texas Instruments – exploitation unknown. The Object Based 3D Imaging is waiting for the Universities to get funds for a spin-out company. It is also being investigated for adaptation to MNR imaging. The RASOR land mine detection has vanished into the MOD. The moving belt variant for QA in food processing has had a successful feasibility study and QinetiQ is negotiating for a development contract with an international company. Only the RASOR breast screening is making progress with a University spin-out company about to start clinical verification trials.
Ralph started his talk with a quote from Rutherford “If you understand your subject you should be able to explain it’s essence to any sympathetic listener with reasonable intelligence, common sense, and no preconceived ideas”. Ralph certainly passed this test and provided us with an excellent talk.
Michael Clinch thanked Ralph for his thought provoking talk. He agreed that “it can’t be done” was a good starting point for research and development and admitted that he had been unaware that CAT-scans used such high radiation levels, citing its use on the unborn child as of particular concern.
Michael Clinch has again supplied us with pictures from our well attended Autumn Luncheon.
Alfred John West (1857-1937) was a film pioneer active from 1897 to 1913 and an award winning marine photographer from the mid 1880s to 1900. His family were all involved in the business founded by his photographer father, (also a Master Carpenter) George West at 97 High Street in Gosport.The following is Alfred's description of obtaining this high speed photo:-
Above: Photo taken by A.J.West in 1897 - courtesy of Siemens UK - from archive sources
Below: plan and elevation of the 'Turbinia'
'It was at this same (1897 Fleet Review at Spithead) Review that a wonderful little vessel named the "Turbinia" appeared, steaming through the Fleet at 35 knots, a speed never before achieved on water. She was the first ship to be fitted with the turbine machinery invented by her owner, the Hon. C. A. Parsons of Newcastle-on-Tyne, and a great sensation was caused by her steaming through the lines at such a speed. Whilst she was at anchor in Portsmouth Harbour, I went aboard and told the owner that I would like to get a snap of his craft going at full speed.
"No one has succeeded yet, although many have tried", replied Mr. Parsons.
"I should like to have a shot at her", I persisted.
"Alright, so you shall!" he said with a smile, "I will make another run through the fleet tomorrow, look out for me between lines A. and B. at noon. That should give you an opportunity."
"I’ll be there, opposite the Flagship", I told him,
Punctually at l2 o’clock there appeared between the leaders of the lines a smother of foam - it was the "Turbinia". As she raced past the Flagship, I was waiting in my launch and took a flying shot of her. When I developed the plate I was delighted to find that I had "got her", and the owner was so pleased with the result that he invited me to take a number of photographs and a cinematograph film of his craft on the Tyne.'
On the afternoon of Wednesday 13th September 45 members were treated to a very authorative talk under the above title by Dr Carolyn Moreton who is a lecturer at the University of the West of England. She is a scientist and psychologist and for 20 years has been running a degree course in forensic science at the UWE, in conjunction with the Police.
She told us that forensic science is a fairly new speciality, the first laboratory in Britain dealing with it having been established in 1935.
We heard that the roles of a scientist are to examine evidence, to write a report and give evidence in court. In recent years these roles have widened to use the evidence to find the culprits, to investigate on the side of the police and to add to the general police intelligence.
A common function is to determine whether a death was due to murder or natural causes, the most noteworthy recent example being the Shipman case. There may be a need to identify drugs by techniques such as gas chromatography or spectrometry. One feature is that the hair may absorb traces of a chemical such as morphine.
In finding who did it, much use is made of the traces left by all contacts. In the case of footprints size, pattern, manufacturer and style may be determined. Modern laminate floors are particularly good for footprint traces. Fingerprints are of course the classic evidence. Details such as those may be used to find different crimes, often leading to prosecutions for multiple offences.
Dr Moreton had much to say about the modern technique of DNA profiling which is very different from fingerprinting. It is one of the strongest forms of evidence using traces from blood, semen, saliva, skin or the hair roots. If there are 6 similar “loci” there is a 1 in 50 million chance that identification of the suspect is not correct, but using 10 similar “loci” as is now usual the chance of a false identification is 1 in 1 billion. The national DNA database now has over 3 million profiles with 355,000 crime scene samples.
Surprisingly only 2% of DNA records are for females. As brothers and sisters have very similar profiles, familial researching can give clues. A DNA profile may give a clue to ethnicity but this is not used for prosecution.
One advantage of all scientific evidence is that it can be examined or re-examined over a period of time and may be evaluated in the light of more than one theory. DNA profiling is the main feature used in solving many “cold cases” since 1995 and particularly since 1999.
Dr Moreton gave many examples of celebrated cases solved in recent years, some of them in the Bristol area.
The many questions asked by the audience gave an indication of the interest generated.
Talk by Stuart Burroughs 11 October 2006
Our meeting on the 11th of October was a talk with the above title by Stuart Burroughs, Curator of Bath Industrial Museum.
Mr Burroughs started by remarking that that Bath was not a very industrial city but for many years Stothert and Pitt had been much the largest industrial employer with 2300 employees at the peak in 1950.
In the earliest days in the late 18th century George Stothert first had an ironmongery business but in 1815 he started his own foundry and became a supplier to the construction industry, iron railings being an early major product. Other items supplied to the civil engineering contractors included iron footbridges for the Kennet and Avon canal, machinery for the Box Tunnel and early cement mixers. By the late 1830’s he was building steam engines and in 1844 Robert Pitt joined the firm and Stothert and Pitt, Engineers and Founders started the Newark Foundry.
At the 1851 exhibition in Hyde Park they displayed a crane which was the first of a great variety for which they became famous. In 1857 they established a new Newark Foundry in Lower Bristol Road and they became renowned for their dock cranes and other machinery.
In 1890 they built their Victoria Works, also in Lower Bristol Road. In 1892 they supplied their first electric cranes for Southampton Docks and in 1914 they developed Titan cranes followed by Hercules and Goliath. In 1912 they invented the Topliss system for loading and unloading ships, this kept the load at a constant level, thereby saving time. During the 1920’s, in addition to cranes they were supplying pumps of all types world-wide.
During world war 2 they built some midget submarines. They continued to prosper but in the 1980’s the company was bought by Maxwells Hollis Group and in 1989 manufacture ceased.
Spares for their many products were still required and the designs were passed to the Vickers Group to make these. A small design staff still remains but assembly is now contracted out to firms around the world.
Mr Burroughs concluded by referring to the current controversy as to whether the remaining building in Lower Bristol Road should be conserved or whether it should be demolished and the site used for a modern technical college sponsored by James Dyson.
We were Shown an excellent set of Photographs of Stothert and Pitt Products.The attendance was 49.
Editors Note:- While searching for images to use with this review I came across the Boulder Bank Light House in New Zealand
The adjacent photo was accompanied by this note "The lighthouse sections were cast by Messrs. Stothert and Pitt, engineers of Bath. They were shipped to Nelson aboard the 'Glenshee'. On 4 August 1862, the oil-fired lamp was lit for the first time by the head lighthouse keeper and brother of the harbour master"
I Find that the lighthouse was decommissioned on 4 August 1982 after 120 years continuous service.I believe Bath can take real pride in the service its industry has given to the world. The next item is a diversion occasioned by searching Naval photographs for cranes
Talk by Tim Ryan
8 November 2006
Members and visitors enjoyed a most enjoyable afternoon when Mr Tim Ryan spoke to us about the history of Aust Ferry and his efforts to preserve this living yesterday so familiar to many of us travelling to Chepstow prior to the Severn Bridge opening on September 8th 1966
Tim Ryan started his talk by covering a general history of the ferry. Ferry’s he told us had plied their trade from earliest times, he cited a ferry price list for 1775 which is now in Bristol museum. The three last ferries were the Severn King and the Severn Queen built in 1931 and for the last few years, the Severn Princess built in Hull in 1959. These vessels were custom built having two independent Leyland 680 Bus engines. Tim had many interesting anecdotes about the history of the ferries, not least the trip from Hull to Beachley which took five days, the only accommodation for the crew of five provided, was a two berth caravan. In operation, the whole enterprise had to pay its way, and this was further illustrated when a Hearse using the crossing, in addition to the normal charge was invoiced a further 1/6d for the coffin.
The whole ferry operation was efficient and served the needs of the day. The crossing took 12 minutes, not counting loading and unloading times. Capacity was 98 passengers and up to 19 cars. Health and Safety was largely left to luck with support from the other ferry if it was available. Only six life belts were provided and presumably thought quite sufficient in the circumstances.
The speaker played an interesting DVD covering various aspects of the history of the Ferry, and these were offered for sale. I can't say they were really good value at £10 as mine was very grainy and jerky. However purchase was in a good cause.
The last days of the sole surviving vessel, the Severn Princess, were rather unhappy, sold to a firm in Ireland, it was used for general carriage of goods which included just about anything. In the absence of a pier, the ferry was run ashore for unloading which for a 98 ton vessel, eventually so damaged the hull that leakage became unacceptable. It was sailed to Kilkieran in Galway Connemara, and during a storm was thrown onto the quay where it as found by Tim Ryan and colleagues.
The talk included details of the ships salvage, its eventful passage back to Beachley and salvage work to date at Beachley.
Enquiry revealing that Health and Safety regulations would preclude necessary licences to sail even if it was in perfect condition, it has been decided to cosmetically restore the vessel for show purposes only. A recent offer by Network Rail of a site in Chester is to be taken up, and the ship will be towed there to form the centre attraction of an exhibition site..
All in all a most interesting afternoon supported by a lively question time, it was well attended and in view of its being very much local history, greatly appreciated by a knowledgeable audience.
Michael C Clinch.
Contributions from members are essential otherwise there is no material to edit. There is a very definite limit to my creative abilities. I am open to suggestions as to items to include. Reports on visits and on talks should provide the bread and butter items. Individual articles on subjects of prospective interest to members will also be most welcome. Between 3 and 1000 words, with or without pictures or photos please!
This is a call for papers and contributions for the next edition of the Newsletter. Do share your interesting experiences past and present with other club members. Your views may not correspond with the views of the Club Committee and we shall say so - but that is not a reason why they can not be published. Contact details are as follows:
Marcus Palmén 4 Knightcott Road,Abbots Leigh,Bristol BS8 3SB telephone 01275-372905
And finally as we have no more meetings this year and the festive season is nearly upon us An Ancient Greeting obtained from the New World
A Merry Christmas and a Happy New Year
To All Readers
The Adoration of the Shepherds Giovanni Girolamo Salvodo 1530's Washington Art Gallery