I am very pleased to be with you on this occasion which gathers annually the friends and admirers of Professor Eva G. R. Taylor to honour her memory. My presence here reflects the globe-circling impact her work continues to have, as more and more people from many disciplines rely on her varied contributions. As for the distance of the echo to her work, I qualify, coming from close to half way around the globe, or from Long. 110° 58′ 08″ west of Greenwich. I have elected to talk about Felipe Bauzá who, on an autumn day of 1823, presented himself to the Royal Geographical Society here in London, some way north and east from his birthplace, Palma de Mallorca, and his port of departure, Gibraltar. For he was one of the Spanish liberals with a price on his head under orders of that treacherous puppet of the Holy Alliance, Ferdinand VII.

This paper was presented at a meeting of the Institute in London on 18 February 1981 with Dr J. F. Kemp in the Chair. Captain Alderton discusses a variety of criteria for assessing economic optimal speeds and shows how sensitive these optima are to such constraints as port time, voyage distance and bunker costs.

The expression ‘optimum’ is frequently used very loosely and one often finds that the factor under consideration is only being optimized with reference to some, not all, of its dependent variables. A truly optimum speed for a ship can only be achieved by considering:

(i) What speeds the ship can actually achieve, taking into account various mechanical constraints, the state of the hull (fouling), the draft and the effect of the weather.

(ii) What speeds we would like the ship to achieve taking into account the costs, the profits and the pressure of schedules.

Captain Barker's paper was presented at a one-day seminar on The Selection and Display of Navigational Information at Sea, jointly organised by the Royal Institute of Navigation and the Nautical Institute in London on 11 December 1980.

It does not seem so long ago since a shipmaster could not do better than proceed at utmost speed, mindful of sea conditions for heavy weather damage and of fog, for a successful conclusion to a commercial venture. Today the cost of bunkers may exceed the income earned on the freight. Commercial organizations carrying their own cargoes have always had to operate at speeds that relate to freight levels, but owners with their ships on charter, who were never very concerned in conserving bunkers, are now more closely scrutinized on the way they operate their ships, and particular attention is paid to the speed-consumption curve.

The year 1981 marks the fourth centenary of the birth of Edmund Gunter who, during his relatively short life, played a dominant role in England in the advancement of navigation. Born in Hertfordshire, of Welsh parentage, Gunter was educated at Westminster School before entering Christchurch College, Oxford, where he graduated BA in 1603; MA in 1606; and BD in 1615, in which year he was presented to the living at St George's, Southwark.

As early as 1603 Gunter had written an account of a ‘New Projection of the Sphere’ which was circulated in manuscript among some of his mathematical acquaintances. This appears to have gained for him the friendship of Henry Briggs, the first Gresham Professor of Geometry and a brilliant mathematician best known for having been first to suggest a table of logarithms to base 10 – ‘common logarithms’, as they are now known.

This paper was originally presented at the Second Symposium on Satellite-Doppler Positioning in Austin, Texas in January 1979.

The application of doppler satellite technology to ice-movement studies requiring high-quality positional determination ( ± 1 m) has proved of great value in remote areas of Canada. Potential oil and gas anomalies in the Arctic Islands, hundreds of kilometres from land, can now be successfully monitored with regard to ice-floe movement by remote methods on an almost daily basis. Extensive field tests conducted in the Calgary area during the fall of 1976 showed that daily movements as small as 1 m could be detected with high-quality satellite receivers using rigorous three-dimensional multi-station computer processing methods.

It has for some years now almost been folklore that the marine traffic situation in the Dover Strait is one of great potential danger. Very considerable efforts have been made to alleviate the situation. There is a complete traffic separation scheme (the first in the world), there is continuous radar surveillance both from England and France, there are routine broadcasts on v.h.f. to warn mariners of any navigational problems, and there is now a system whereby certain ships report-in. Concurrently with all this activity, the accident rate has dropped significantly over the last decade, especially in fog, and it is a reasonable inference that the reduction in the number and severity of accidents is attributable to this activity.

But patterns of navigation change, and it is necessary for marine administrators to be aware of problem areas as or before they arise so that marine management measures can be introduced when appropriate. Factors to be taken into account are the volume and characteristics of the traffic, the difficulty of navigation and the accident record. One of us has drawn attention to the traffic situation off East Anglia and suggested that a prima facie case for some remedial measures had been made. This paper examines the available evidence in more detail.

First, an account is given of the accident record in the area under consideration (Figs 1, 2) over the last 10 years. Both the numbers and severity of collisions and strandings are discussed.

Following the Amoco Cadiz disaster in 1978 proposals were put forward, and ultimately accepted by IMCO, for a revision of the traffic separation schemes off Ushant and the Casquets, the broad effect of which was to keep large tankers (and those carrying hazardous cargoes) further off the French coast. The modifications came in for some criticism and recent Anglo-French proposals have now secured IMCO agreement. Prior to that a purely United Kingdom working group sought to formulate a comprehensive and continuous routing scheme for the whole English Channel.

Captain Cockcroft who, as an observer for IAIN at IMCO and as RIN representative on the UK working group on Channel Routing, has played a leading part in these discussions, here describes some of the problems and considers issues raised by concepts such as ‘areas to be avoided’, and finally, within the context of traffic separation in straits, proposes alterations to the Collision Regulations which govern the crossing of traffic lanes and the use of inshore traffic zones.

In the title to this paper I have deliberately used the plural, for I do not think it possible that the compass was only invented in one country and knowledge of it transmitted from there to other parts of the world. It is much more likely that the possibilities of its use, not necessarily for purposes of marine navigation, were discovered in several parts of the world, that some who knew of it transmitted it to their neighbours, but that in some areas the original knowledge was lost again. Of course such inventions may have had forms very different from the compass as finally used.

The first definite European account of the compass is contained in the writings of Alexander Neckam (1157–1217), about A.D. 1187. In De Utensilibus he wrote: ‘Qui ergo munitam vult habere navem…habeat etiam acum jaculo suppositam; rotabitur enim et circumvolvetur acus, donec cuspis acus respiciat orientem sicque comprehendunt quo tendere debeant nautae cum cynosura latet in aeris turbatione.’ The translation of this which I accept is as follows: ‘Therefore he who wants to have a well-equipped ship…let him also have a needle placed under a dart; for the needle will rotate until the point of the needle looks towards the East, and thus sailors perceive in which direction they ought to go, when the Little Bear is hidden in disturbed weather’. It has been suggested that in this passage ‘donec cuspis jaculi respeciat’ was probably intended for ‘donee cuspis acus respiciat’.

In this paper Claud Powell, formerly of the Decca Navigator Company, discusses the antecedents of modern radio position-fixing systems whose position lines are of hyperbolic form. The paper was presented at an Ordinary Meeting held in London on 22 April with Rear-Admiral D. W. Haslam in the Chair.

Until very recently in human history, the fixing of position for navigational and kindred purposes depended principally upon the measurement of angles. An escape from the limitations of this essentially visual process had to await the development, through advances in electrical and later in electronic engineering, of what E. W. Anderson has termed the ‘timing of waves’. This classification covers virtually all the non-visual methods of deriving a line of position, for example the measurement of range by timing the roundtrip of a signal travelling at a known speed to a reflector or transponder and back; the measurement of ‘pseudo-range’ by comparing the times of signal transmission and reception according to local clocks; and the differential measurement of range to two known points some distance apart by timing the interval between the reception of synchronized signals transmitted from those points.

This paper was presented at a meeting of the Institute in London on 21 January 1981 with W. H. McKinlay in the Chair. The views expressed do not necessarily represent CAA policy, but Mr Attwooll discusses the derivation of fuel-uplift requirements from considerations of safety and regularity of the flight, using additional information on the probability of various adverse contingencies such as headwind or ATC delay. Methods of safely reducing fuel reserve requirements are discussed, including improvements in navigation and the on-board decision-making process.

This paper, which was presented at an Ordinary Meeting of the Institute in London on 18 March 1981 with Dr J. F. Kemp in the Chair, outlines the scope for using modern programmable hand-held calculators at sea, discusses the functions and facilities required for navigation and describes some of the models now available.

For many years the basic instruments for navigation have been the compass, chart, sextant, log and chronometer; an advanced scientific calculator should now be added to the list. Indeed, this type of calculator should form part of the personal navigation equipment of every navigator—marine or air, military or civil—because the way to get the best out of a machine is to have one of your own; you will seldom get the best out of any machine which is shared.

Recent growth in air-traffic movements is causing severe traffic congestion problems in terminal areas and en route. To meet these demands for more effective and safe utilization of airspace, separation standards in an air-traffic-control environment are being studied by the Review of the General Concept of Separation Panel (RGCSP) of the International Civil Aviation Organization.

One of the most effective ways of evaluating separation standards would be a mathematical method using a collision-risk model, for which we require data on the navigation accuracy of current aircraft as one of the parameters. At present, the data on navigation accuracy in the vertical dimension (height-keeping error) do not permit us to derive any definite conclusions on the distribution of navigational errors. In order to survey height-keeping errors we have developed a simple height-finding radar system, the Navigation Accuracy Measurement System (NAMS), based on a curve-fitting method. Thanks to this principle, NAMS has an advantage in its comparatively lower cost and simple structure.

The system consists of an antenna whose radiation pattern is a fan beam, a transceiver, a digitizer and a mini-computer. The antenna rotates about a horizontal axis and scans aircraft flying overhead. The height of an aircraft is estimated by processing the data obtained over several scans, using a mini-computer. This paper first outlines the characteristics of NAMS and then gives results of evaluation tests on its accuracy.