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First, I wish to thank Her Majesty's Government for allowing time for this Bill to be given a Second Reading. It is also a happy coincidence for me that the day selected is the one on which the noble Lord, Lord Steel of Aikwood, took his seat in your Lordships' House. I trust that it will not be considered out of order if I say now that I have no doubt that the House will benefit in years to come from the contributions that he will make to it, in just the same way as I have benefited from his friendship and good counsel these past 40 years. I wish the noble Lord well in his new surroundings.
The Co-ordinated Universal Time Bill, which is before us tonight, is in part a short technical Bill which will correct an oversight in the Act of Interpretation 1978. This oversight could possibly be due to this particular Act of Parliament having been passed in Committee upstairs rather than on the Floor of your Lordships' House. Nevertheless, the Co-ordinated Universal Time Bill will also be in part a correction of the popular misconception that when a clock, watch or any other timing device is set it is set to the GMT time-scale. This is not the case. The BBC "pips" on the radio, or the speaking clock service provided by BT, do not transmit GMT, but co-ordinated universal time, or, as it is more generally known, UTC.
It is quite impossible, for the reasons which I am about to give, to set a watch or clock to Greenwich Mean Time. However, the legal definition of time, as set out in Chapter 9(1) of the Interpretation Act 1978, is still Greenwich Mean Time. The Bill before you simply replaces GMT, which has been a redesignated time-scale since 1975, with UTC, the current world time-scale for all civil and legal use.
Secondly, in the same year--1975--it was also agreed in principle by the International Weights and Measures Act, or BIPM--which, for those who are interested in these things, stands for Bureau International des poids et mesures--that Co-ordinated Universal Time (UTC) should become the accepted time-scale for civil and legal use throughout the world. I understand that the United Kingdom was a signatory to this agreement at the time.
Meanwhile, my Lords, the Co-ordinated Universal Time Bill reaches back through the Interpretation Act 1978 to the original Definition of Time Act 1880. This Bill is its legal antecedent. Furthermore, the Bill before us enshrines universal principles of the measurement of time and place from Greenwich, as was agreed in the First International Meridian Conference 1884. This is its scientific antecedent.
I am pleased to report that when the noble and learned Lord the Master of the Rolls was made privy of the contents of the Bill before this House he was able to indicate to me in writing that he considered the change from GMT to UTC "a sensible" measure. I hope and trust Her Majesty's Government will take the same considered view during the Bill's passage in the other place.
In supporting this change-over in the legal time-scale, I wonder whether the noble and learned Lord was aware that he was merely carrying on a long tradition of his profession's interest in horology? No more so is this apparent than in the Palace of Westminster, where the
I hope that the noble Earl, Lord Shannon, who I am glad to see will be speaking after me, will remind noble Lords of the day when Lady Shannon made the presentation of an exact model of the gravity escapement to the Palace of Westminster. It is now on display in the clock tower for the benefit of all to see.
The reason I have mentioned the Great Clock is that I can personally vouch that since the mid-1970s it has always been set to UTC not GMT. I can also say that when Big Ben, which is the hour bell named after Sir Benjamin Hall (who was Commissioner of the Office of Works at the time), strikes in the new millennium it will be UTC time not UT or GMT. This will be regardless of whether or not this Bill, which changes the legal time-scale from GMT to UTC, ever reaches the statute book.
The question will no doubt arise as to why there is any necessity to change the law from GMT to UTC when in practice the maximum difference between the two time-scales (UTC and UT) can never exceed 0.9 of a second. This question cannot be answered properly unless there is, first, a clear description of Co-ordinated Universal Time (UTC) and Universal Time (UT) and the fundamental differences between them explained. I shall use the initials from now on, which will be much easier.
In 1967 the General Conference of Weights & Measures adopted the fixed atomic second using the regular vibrations of caesium-133 atoms in a clock at sea level as a regulator. These atomic clocks form the basis of International Atomic Time (TAI) and are accurate to less than one second in a million years. In 1967 the new atomic time-scale replaced ephemeris time, which, fortunately, does not concern us this evening.
In 1975 the International Conference of Weights and Measures (BIPM) to which I have already referred, recommended that Co-ordinated Universal Time be derived from the more accurate TAI and become the accepted civil and legal time-scale for all nations. UTC would be transmitted from more than 200 atomic clocks around the world with an accuracy of plus or minus two milli-seconds. Most industrialised countries, with the exception of the United Kingdom, have accepted this recommendation made 22 years ago.
I believe the decision to accept this recommendation of the BIPM can no longer be postponed. The reason for this is that in the not-too-distant future all clocks, PCs and other IT devices, will almost certainly become directly linked to the UTC time-scale through their ability to receive UTC "pips" direct.
This could mean, by the turn of the century that all legal documents, (including birth or death certificates) will have as a matter of course UTC time with tenths of a second accuracy printed on them.
However, if the legal time-scale continues to remain as UT--that is, old GMT which is not accessible by the general public and which can only be accurate to the nearest second--many unnecessary problems could arise in the future regarding tax claims, to name but one. There could also be increasing problems with law and business conducted over the Internet if there were apparently two differing legal time-scales.
Some noble Lord might ask whether the two time-scales could not be reduced to one. This would avoid the current confusion and therefore the need to change the one which has served the country and its public so well for the past 117 years. The reason why this cannot be done is that UT--that is old GMT since 1975--is a general designation of all time-scales based on the Earth's rotation and therefore becomes ambiguous in that the term represents more than one time-scale.
The UT time-scales are of differing refinement and include UTO, which is the mean solar time of the prime meridian obtained by direct astronomical observation. There is UT1, which is UT0 corrected for the Earth's polar variations, and then there is UT2, which is UT1 corrected for the seasonal fluctuations in the Earth's rotation rate. Your Lordships will see from the complexity of this that these matters do not belong in the public domain of timekeeping.
The rate of the earth's rotation is calculated by the International Earth Rotation Service--IERS--which provides the information regarding the difference between UT and UTC which decides when to insert a leap second as and when the difference between the two time-scales approaches 0.9 seconds. Incidentally, such a moment will occur at 1 a.m. BST on 1st July this year when it has been decided that UTC, which is transmitted by atomic clocks around the world, will add one extra second in order to match the slowdown of the Earth's rotational speed. This process is currently the scientifically-acknowledged basis for all time on Earth.
I hope that, by going into some detail of the scientific work that goes on behind the scenes to produce UT--old GMT--it will be recognised that UT cannot possibly be the basis of an accurate or predictable time-scale that is suitable for use by the legal profession or the general public.
In short, I am saying that atomic time with a fixed second is best suited for civil and legal time and is accurate to about one second in a million years, whereas Universal Time--old GMT--based on the Earth's rotation (which can only be calculated by scientists) is best suited for astronomy and related subjects.
UT can never be as accurate as UTC in that any small variation in the Earth's rotational speed, which is, incidentally, about 1,030 kilometres per hour at the point at which we are sitting cannot be anticipated as the Earth makes its annual journey around the Sun at speeds approaching 106,000 kilometres an hour. Meanwhile,
I should now like to draw your attention down to the Earth's surface, in particular to Clause 2 of the Bill before us. Noble Lords will note that in that clause, I am attempting to ensure that by changing GMT (UT) to UTC, the scientific uses of UT will not be affected when applied to other direct and indirect references to GMT in other Bills, for example, the Summer Time Act 1972. I am taking advice on this point and it may be that some minor amendments may have to be made in Committee. However, perhaps I may explain that the Bill changes all references in other Bills from GMT to UTC. I believe that that does not affect the law as it stands but I am taking advice and if necessary, I shall produce the appropriate amendments in Committee.
I made mention in my introduction that this Bill enshrines the universal principle that the measurement of all time and place on the Earth's surface will be taken from the prime meridian at Greenwich. This was agreed by the First International Conference held in Washington DC in 1884.
The time and method of calculation of the universal day is precisely what I have described as UTO; that is, the mean solar time of the prime meridian obtained by direct astronomical observation and corrected to mean midnight on zero. That was all that was available scientifically at that time. If they had had atomic time or UTC available to them then, they would have undoubtedly started the Universal Day on UTC and not UT. That is the point I am trying to make.
The reason I am looking backwards in time to those events and definitions in so much detail is that as we approach the millennium, many others will be doing likewise. The previous Administration and the new Government have both agreed to spend an incredible sum of public and private money--I think approaching £600 million--to build a monumental dome at Greenwich in order to celebrate the occasion.
Furthermore, I understand that this complex is to be built along the prime meridian with 12 satellite pavilions, the main theme of which will be the history and dimension of time. As a part-time horologist, I can only applaud such inspiration and foresight. However, I sincerely hope that on completion, all time will be displayed correctly as UTC and not pretending to be GMT, as is the case today outside the Maritime Museum at Greenwich.
When the eyes of the world are focused on Greenwich and its history at the start of the new millennium, it would be a very sad event indeed if we, as a nation, failed to display the correct time when the moment came.
I feel that a theme park is different from a museum. Science as shown in a theme park need not necessarily be real science. But we are very proud of the Greenwich Museum and the names of the people associated with it--Herschel, Harrison and Tompion--because they were all British. They were scientists. They were not part of a theme park. I feel that we should try to get the time right as the millennium approaches.
The Astronomer Royal, Professor Sir Martin Rees, having had sight of this Bill, was kind enough to indicate to me that its passing would be a service to the community at large. I have received support from many other quarters including the Master of the Worshipful Company of Clockmakers and the British Horological Institute.
The only hesitations I have met so far about the effect of the Bill have been from those who might regret the passing of the historic term "Greenwich" from the national time-scale. I share a certain sadness for the same reason, and wonder if a new term for the world time zones including the word "Greenwich" can be devised in time for the millennium. That is not something for the law or for your Lordships' House to decide. But the scientists who got us into this problem may be able to help us in that direction. Meanwhile, the abbreviation GMT would continue to be used by the BBC World Service and BT to describe the world time zones once this Bill was passed and until a replacement term was found.
I have suggested in an article on this subject, which was printed in the May edition of the Horological Journal and which is available in your Lordships' Library that "Greenwich Meridian Time" might be adopted for that purpose. However, I have been persuaded subsequently that this may create confusion due to having the same abbreviation as Greenwich Mean Time. Other suggestions have been made to me including "Greenwich World Time" which I rather like. That is another possibility to be considered. If this Bill manages to reach the statute book I hope that something along those lines will be discussed outside the Palace of Westminster, but nevertheless in time for the millennium.
The Earl of Shannon: My Lords, the House should be very grateful to the noble Lord, Lord Tanlaw, for introducing this Bill and also for the quite brilliant exposition he gave of why it is needed as we stand today.
Here we are dealing with the inevitable and irresistible march of history and, as the noble Lord suggested, the possibility of a legal tangle which is just waiting to happen. We have had a very brilliant exposition of the technical reasons but I wonder whether, in order to put the matter into context, we might perhaps have a short historical sketch. Every system quantifying time must have a standard or a time-base from which to operate. To primitive man, the sun in its apparent passage appeared to be a fairly regular traveller across the heavens, and was of course the obvious choice.
About 4,000 years ago sundials were developed to show, more accurately than just the guesswork of looking at the heavens, the divisions of the day as the sun moved round. With the advent of mechanical horology, and especially the pendulum, as the time-base, which operated conveniently at night as well as by day--which the sun did not do--it then started to become apparent that the sun itself was not so regular. That is because the earth does not go round the sun in a perfect circle, but in a rather lopsided, egg-shaped, elliptical course, making the sun either fast or slow by round about a quarter of an hour at some times in the year. That led to the preparation of a table of constants and that became known as the Equation of Time and was used by those who checked their clocks by sundials. Noble Lords should remember that there were no BBC pips in those days; indeed, one had to go out to one's sundial and calculate whether the sun was fast or slow and then check one's clock accordingly. One could then make the necessary corrections to give an average or mean time.
I suspect that in the 18th century there were very many more people in this country who understood the Equation of Time and how it came about than there are today. Indeed, if one mentioned the Equation of Time, how many people in the street would have the slightest idea of what one was talking about? Sundials, even when corrected, gave the local time, which varied across the country depending of the longitude and the place where the sundial happened to be. The increasing speed of transport over the years, first by stagecoaches and then by trains, started to show that journeys at the same speed from east to west appeared to be quicker than the same journey at the same speed in the opposite direction. Thence, legally, we had to have a national time which applied over the whole country, based on the Zero longitude of Greenwich. That became known
However, this was still a calculated average. As the pendulum with temperature and barometric compensation became more accurate, it started to show that the dear old earth did not make such a steady, albeit egg-shaped, course around the sun but tended to wobble a bit. Hence we had Polar Variation--another additive to the equation, small but significant. Now we have an even more nebulous, more averaged time standard--which is still called Greenwich Mean Time--based on the earth wobbling around the sun. Moreover, the pendulum itself was related to the earth and its timed swing depended on gravity. But that is not constant, as it varies up hill and down dale and according to whereabouts one is on the surface of the earth.
Fortunately, in this century, we saw the emergence of entirely new time bases which were totally divorced from the old earth/sun relationship with its much-manipulated and much-averaged attempts to get an accurately standard product. I refer of course, first, to the vibrations of a quartz crystal of certain dimensions, though these were still rather temperature sensitive. Secondly, in this century, we have, as has been mentioned, the resonance of the caesium atom--a fixed, definitive and totally accurate, given a million years, time-base which is devoid of all the complicated averaging and general messing about inherent in trying to make the best of the old earth/sun relationship into Greenwich Mean Time or Universal Time.
One may ask: "Why bother to make legal allowances for such small variations?" With the exponential advances in things such as computer technology, where millionths, and even smaller fractions, of a second are of importance, surely in the not too far distant future there is the possibility that legal cases could emerge where a clear and distinctive standard of time will be an essential requirement. We had better be ready for it now and not try to duck the issue in the belief that we can wait until the actual disaster happens.
Our present so-called Greenwich Mean Time signals to which the noble Lord, Lord Tanlaw, referred, are already having to be corrected by Co-ordinated Universal Time, although, legally, GMT itself is just an outdated and somewhat indefinite standard in today's world. Of course, as a matter of national pride, we wish to try to retain something of the old term "Greenwich Mean Time"--indeed, the noble Lord, Lord Tanlaw, suggested one or two possible alternatives--but it is still possible to keep Greenwich, and perhaps something to do with mean time, for normal everyday use.
For this purpose, we do have an exact precedent. Traditionally, a very early English king defined the English yard as the distance between his nose and the tips of the fingers on his outstretched right arm. That was probably sufficiently accurate for his day as a standard, provided that His Majesty could be retained looking straight to the front. It was later defined as the distance between two scratches on gold plugs in a metal bar at a definite temperature. That was getting a bit more accurate, but an even greater accuracy was called for in
Therefore, why not have Greenwich Mean Time or something similar although, for legal definition, time could be more accurately defined by the atomic time of Co-ordinated Universal Time? I believe that Her Majesty's Government ought to welcome the opportunity offered by the Bill of getting into today's world and the new millennium as regards a legal time standard.
Lord Fraser of Carmyllie: My Lords, a sorry rumour reaches me that in their rush to clumsy constitutional change the Government propose that the role and the breadth of the participation of the Cross-Benchers in this House might be restricted in the same way as it is proposed that the contribution of hereditary Peers might be restricted. Having listened to the noble Lord, Lord Tanlaw, and the noble Earl, Lord Shannon, I hope that the Government might reflect more deliberately upon that because if there is a worthwhile contribution that your Lordships' House might offer more generally to the deliberations of the nation, it would seem to me that this is such an occasion.
This is a subject that does not immediately command the attention of those who are travelling home on the Tube tonight or on buses the length and breadth of the country. But given the variations that have grown up around the world, it seems to me entirely appropriate that a matter such as this should be discussed in your Lordships' House, and indeed that the noble Lord's Bill should be given a Second Reading.
I recall with something approximating to horror the exchange that I had with the noble Lord on 27th November of last year. That debate is recorded at cols. 257 to 260 of Hansard. Subsequent to that exchange at Question Time I was advised by a number of noble Lords that it was regarded as being one of the most fascinating and erudite exchanges that had taken place in your Lordships' House. I wish I could claim that the erudition of that exchange was entirely my own work. However, I have to say in all modesty that I owed my transient grasp of this extraordinarily complicated subject of Greenwich Mean Time, Co-ordinated Universal Time and Atomic Time, not just to the erudition of my officials in the DTI. That erudition was remarkable but it was exceeded only by their patience in explaining to me what the subject was all about. I cannot say that we quite had resort to the matchsticks that the late Lord Home was considered notorious for as regards his grasp of economics. But certainly round my table a number of coffee cups were moved rather quickly to explain to me exactly what were the difficulties in trying to reconcile the erratic elliptical
The reconciliation of those different approaches to time involves complex issues. I do not believe that I have the expertise to understand them in their entirety. I indicated to the noble Lord during the exchange on 27th November that such was the correction that was allowed in Co-ordinated Universal Time in relation to Greenwich Mean Time, that it did not seem to me for legal purposes--which is what we are primarily concerned with in the Interpretation Act to which the noble Lord addresses his amendment--there was any necessity to adjust Greenwich Mean Time. As I said then, I was astonished to discover that some 29 leap seconds had been introduced into our calendar since 1958. That seems to me a rather remarkable extension of time. However, it did not seem to me to offer any significant legal impact or change. For that reason I suggested that the then Government would not support the change that the noble Lord now proposes.
From these Benches that remains our view. However, I have listened to what the noble Lord has said. I agree with the noble Earl that it was a quite extraordinary exposition. I cannot say that I understood every passing phrase of it in its entirety but it has been an extremely interesting exposition of why it might be desirable to introduce a change. I regret that there are not more noble Lords present in your Lordships' Chamber to grasp what is being proposed. I certainly suggest that there should be an opportunity further to discuss this Bill in your Lordships' House.
Lord Haskel: My Lords, this has been a fascinating debate. I did not quite understand the reference of the noble and learned Lord, Lord Fraser, to our restraining the Cross-Bench Peers in your Lordships' House. I start by congratulating the noble Lord, Lord Tanlaw, on his tenacity in returning to this subject and on the erudition with which he introduced it. He may recall that this is not my first brush with Co-ordinated Universal Time because I participated in the erudite exchange of 27th November to which the noble and learned Lord, Lord Fraser, referred. This is rather like a re-run of that exchange but our roles are reversed.
In his speech moving the Second Reading of this Bill the noble Lord, Lord Tanlaw, has most eloquently explained the complexities of the difference between Greenwich Mean Time and Co-ordinated Universal Time and why the time may not be exactly what we think it is. He is an horological expert. I congratulate him on that. I understand that he was interviewed this evening on local radio at Greenwich. People there seemed to be not too concerned about whether the time should be Co-ordinated Universal Time or Greenwich Mean Time.
One point to make clear at the outset is that this Bill will not in any way outlaw the use of Greenwich Mean Time, nor will it have any effect on Summer Time. The noble Earl, Lord Shannon, told us that the earth is a cog in a giant clock. Its rotation regulated our days and its
Improved communications and better clocks revealed another problem with using a sundial as a clock. The local time according to the sun in different places depends on how far east or west they are of each other. Therefore, if the trains were to run to any sort of timetable, and if it was to be clear whether the assizes were to convene at the time shown on the judge's watch set in London or at the time on the town hall clock, it was necessary to adopt a common timescale. The timescale adopted in Great Britain was that based on the local time, according to the mean sun at Greenwich.
The use of Greenwich Mean Time for scientific purposes duly died out, although the term lives on in everyday parlance. One reason the scientific community no longer uses the term GMT--as the noble Lord, Lord Tanlaw, explained to us--is that we are no longer really sure what GMT is. However, Universal Time is hardly more certain. It has three separate definitions depending on which corrections have been applied for the earth's rotation. The noble Lord told us about that.
The noble Lord, Lord Tanlaw, and the noble Earl, Lord Shannon, told us about the development of atomic clocks at the UK's National Physical Laboratory in the 1950s. These opened the way for yet another more stable timekeeping method and subsequently a new definition of the second. The simple timescale based on atomic clocks is International Atomic Time. This scale is measured by the weights and measures bureau using data from the 272 clocks in 43 national laboratories, to which the noble and learned Lord, Lord Fraser, referred.
Like mechanical clocks before them, atomic clocks revealed another problem with using the sun to set our timescale. Because of the irregular motion of the earth, International Atomic Time moves out of step with Universal Time. To get round this difficulty, leap seconds are occasionally added or subtracted from International Atomic Time to keep it within 0.9 seconds of one of the three forms of Universal Time. The timescale created in this way is Co-ordinated Universal Time--the timescale selected by the noble Lord. As he told the House, to date, 30 leap seconds have been added from the reference point for the beginning of International Atomic Time since 1st January 1958. Another will be added at the end of this month.
The effect of the Bill will be to replace a reference in the Interpretation Act to a timescale which we know reasonably well and which is familiar with one that we know very well but which is less familiar. It does have the advantage of referring to Greenwich, the home of astronomy and navigation, and there is no evidence that the continued use of GMT creates a problem. We actually use UTC but, confusingly, call it GMT.
However, the Bill would not in any way outlaw Greenwich Mean Time, nor would it prevent its use in Acts of Parliament or for legal purposes. The rationale for the provision in the Interpretation Act is merely to establish the conditions which apply should there be no specific statement as to the timescale to be used. The Bill would increase certainty in such circumstances by specifying Co-ordinated Universal Time rather than the less certain Greenwich Mean Time. In situations where the very small difference between Co-ordinated Universal Time and Greenwich Mean Time matters, it would be wise always to make an explicit reference to which is intended. For legal purposes that would be necessary. Nor will the Bill affect the move to summer time and back each year. The Interpretation Act will, as now, provide for the one hour shift.
Lord Tanlaw: My Lords, I thank all noble Lords who took part in the debate. I appreciate that this type of contribution is extremely difficult to listen to, for it is complicated. I have tried to simplify the information without distorting it. The debate has been positive and I am grateful for the contributions and the apparent support for my Bill.
I should like to say a brief word to the noble Earl, Lord Shannon, on the Equation of Time. I remember as a boy looking at a sundial and finding that, having set it correctly, after about a week or a month it moved. I always thought that the gardener had moved it. I did not know that it was the sun. That was probably my first lesson on how we relate to nature and the celestial mechanics that I mentioned. It is an important matter, for a whole number of reasons.
The noble and learned Lord, Lord Fraser of Carmyllie, as did the noble Lord, Lord Haskel in replying, made the point that, if there is such a fine difference in the time, perhaps we should merely clarify which timescale is being used for the purposes of legal documents and so on.
The driving force behind my Bill has been that of the first conference on longitude in Washington: the universal day and universal time. It all began with the railways. As the noble Earl, Lord Shannon, said, GMT had to be introduced as a timescale in order to enable everyone to catch the trains. Today we have the Internet, which almost overnight has reduced the world to the global village about which people used to talk. For the cost of a local call it is possible to talk to anyone in the world and become involved with that person in great detail, whether legal or technical. Everyone is a neighbour now.
For the same reason that the universal day and universal time were considered in 1884, it is essential that we all have the same timescale. The systems on our PCs and computers are quite inaccurate at present, but they will soon indicate the same time. That is why we should address our minds to the matter, and why in this country we should be prepared, so as not to be at any disadvantage. This matter is not comprehended by either the legal profession or those who conduct business.
I saw a little on television about Greenwich--I was not there. I am worried by the lack of concern at Greenwich regarding the device on the Greenwich Meridian giving the wrong information. It is producing UTC, but says it is producing Greenwich Mean Time. For children who want to learn science and want to learn about the world and nature, as I tried to explain in my contribution tonight, the fundamental difference between those two timescales is fascinating. I believe that children in the future will find it fascinating when they understand it. I do not believe that they want a "quick fix" answer because they have been to Greenwich and have seen something saying "Greenwich Mean Time". The subject is far more exciting than that. If the noble Lord's Government are keen on education, as I am, perhaps this measure will be examined with a view to helping in education and in the encouragement of scientific thinking among our young people.
Once more, I am very grateful for the support expressed and the contributions made. I have every hope that, with the help of this House, the Bill will at least proceed to its next stage. I ask noble Lords to give the Bill a Second Reading. I commend it to the House.
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