Book review: The Technical History of the Beginnings of Radar
2
purpose for which goods are required and has relied on the seller's skill (n) What is the proper law of a contract (o) What are the surrounding circumstances of a con- tract (p) Whether an intention has been evinced not to perform a contract (q) Whether a transaction formed part of a course of dealing (r) Whether damage amounts to 'fair wear and tear' (s) Whether the bulk of goods corresponds with the sample (t) The customary meaning of words (u) Whether a representation was made. 9.2 Mixed conclusions of fact and law (a) Waiver and estoppel (b) Frustration (c) Causation (d) Custom (e) Agency (/) Damages (g) De minimis. 9.3 Conclusions of law (a) The construction of a charterparty or a contract (b) The interpretation of a statute (c) Whether a buyer is entitled to reject goods (d) Whether a contract has been varied (e) Whether a term should be implied in a contract (/) Whether a term of a contract is a condition or a warranty (g) Whether a contract has been repudiated (h) Whether there has been accord and satisfaction. Book review The technical history of the beginnings of radar S.S. Swords Peter Peregrinus, 1986, 325 pp., £36.00 ISBN 086341043X Radar (radio detection and ranging) was not the inven- tion of a single individual, but was developed by hundreds of scientists and engineers in about ten coun- tries. The birth of radar, which occurred around 1935, in the major powers, was shrouded in secrecy and was the child of physics and electrical engineering. It arrived in time for World War II, in which it played a major role and transformed warfare. Quite a number of histories of radar could and have been written from different view- points, such as those of the military historian, or of the student of electronic warfare, or by an analyst of the role of centrally organised scientific research and technical development. Sean Swords, who is a lecturer in Engineer- ing Science at Trinity College, Dublin, describes the tech- nical history of radar, and has written an excellent record of the salient events in its evolution which occurred both prior to and during the 1930s in various countries. He concludes his history with the invention of the cavity magnetron as an efficient generator of microwaves in 1940, which was to lead to many new radar develop- ments wherever a narrow beam of electromagnetic waves was required. The book opens with a short discussion of the nature of radar, and the physical principles underlying pulse radar systems are discussed in some detail. The principal forerunners of radar dating from the beginning of the century are treated in chronological order, and it is emphasised that the possibilities of radar are, in a sense, inherent in the properties of electromagnetic waves. The emergence of radar in the UK, Germany, USA, France, Italy, Japan, Holland and Hungary, is then examined and numerous references to original papers and reviews are given. The story in Britain is then selected for more detailed attention: here the political and technical back- ground to early-warning radar systems is treated in some depth, as is the emergence of the early centimetric air- borne radar for use by the Royal Air Force. There is a brief discussion of the origin of the magnetron and its history up to the invention in 1940 by Randall and Boot, working at Birmingham University, of the resonant cavity magnetron. Finally, there are a number of appen- dixes which are of historical and technical interest. Perhaps the first suggestion of radar was presented by Nikola Tesla, in the USA, who in 1900 discussed the possibility of employing radio waves not only to detect but also to measure the movement of distant objects. 1904 saw the application by Christian Hulsmeyer in Germany for a patent for his telemobiloscope which was a transmitter-receiver system for detecting metallic objects by means of electrical waves. The apparatus was designed principally as an anticollision device for ships and apparently did work quite successfully. In 1922, Marconi addressed the American Institute of Electrical Engineers and suggested to his audience the possibility of equipment that would be able to give warning of the pre- sence and bearing of ships in fog or darkness, even though these ships were not provided with any kind of radio. Also in the USA in 1922, A.H. Taylor and L.C. Young, carrying out VHF propagation experiments at 60 MHz, obtained reflections from buildings and a wooden steamer. Experiments of G. Breit and T.A. Tuve in 1925 demonstrated the existence of a reflecting iono- spheric region in the upper atmosphere, and are invari- ably cited wherever the history of pulse radar is recounted. Prior to this American work, Professor E.V. Appleton and M.A.F. Barnett of Britain had demon- strated the existence of a sky-reflected wave. In 1931, using 50 cm waves, W.A.S. Butement and P.E. Pollard carried out successful experiments on the location of ships on the River Thames. L. Young and Hyland of the American Naval Research Laboratory also carried out reflection experiments at distances up to 10 mile from the transmitter; this occurrence laid the foundation of radar research in the USA, which rapidly expanded with the immense scientific and industrial resources of that country. Just as television, whose technology is akin to radar in many respects, became a working reality in the late 1930s, so too did radar. It was assisted on its way in several countries by military needs but, like television, it IEE PROCEEDINGS, Vol. 134, Pt. A, No. 4, APRIL 1987 349
Transcript of Book review: The Technical History of the Beginnings of Radar
purpose for which goods are required and has relied onthe seller's skill
(n) What is the proper law of a contract(o) What are the surrounding circumstances of a con-
tract(p) Whether an intention has been evinced not to
perform a contract(q) Whether a transaction formed part of a course of
dealing(r) Whether damage amounts to 'fair wear and tear'(s) Whether the bulk of goods corresponds with the
sample(t) The customary meaning of words(u) Whether a representation was made.
9.2 Mixed conclusions of fact and law(a) Waiver and estoppel
(b) Frustration(c) Causation(d) Custom(e) Agency(/) Damages(g) De minimis.
9.3 Conclusions of law(a) The construction of a charterparty or a contract(b) The interpretation of a statute(c) Whether a buyer is entitled to reject goods(d) Whether a contract has been varied(e) Whether a term should be implied in a contract(/) Whether a term of a contract is a condition or a
warranty(g) Whether a contract has been repudiated(h) Whether there has been accord and satisfaction.
Book review
The technical history of the beginnings of radarS.S. SwordsPeter Peregrinus, 1986, 325 pp., £36.00ISBN 086341043X
Radar (radio detection and ranging) was not the inven-tion of a single individual, but was developed byhundreds of scientists and engineers in about ten coun-tries. The birth of radar, which occurred around 1935, inthe major powers, was shrouded in secrecy and was thechild of physics and electrical engineering. It arrived intime for World War II, in which it played a major roleand transformed warfare. Quite a number of histories ofradar could and have been written from different view-points, such as those of the military historian, or of thestudent of electronic warfare, or by an analyst of the roleof centrally organised scientific research and technicaldevelopment. Sean Swords, who is a lecturer in Engineer-ing Science at Trinity College, Dublin, describes the tech-nical history of radar, and has written an excellent recordof the salient events in its evolution which occurred bothprior to and during the 1930s in various countries. Heconcludes his history with the invention of the cavitymagnetron as an efficient generator of microwaves in1940, which was to lead to many new radar develop-ments wherever a narrow beam of electromagnetic waveswas required.
The book opens with a short discussion of the natureof radar, and the physical principles underlying pulseradar systems are discussed in some detail. The principalforerunners of radar dating from the beginning of thecentury are treated in chronological order, and it isemphasised that the possibilities of radar are, in a sense,inherent in the properties of electromagnetic waves. Theemergence of radar in the UK, Germany, USA, France,Italy, Japan, Holland and Hungary, is then examined andnumerous references to original papers and reviews aregiven. The story in Britain is then selected for moredetailed attention: here the political and technical back-ground to early-warning radar systems is treated in somedepth, as is the emergence of the early centimetric air-borne radar for use by the Royal Air Force. There is abrief discussion of the origin of the magnetron and its
history up to the invention in 1940 by Randall and Boot,working at Birmingham University, of the resonantcavity magnetron. Finally, there are a number of appen-dixes which are of historical and technical interest.
Perhaps the first suggestion of radar was presented byNikola Tesla, in the USA, who in 1900 discussed thepossibility of employing radio waves not only to detectbut also to measure the movement of distant objects.1904 saw the application by Christian Hulsmeyer inGermany for a patent for his telemobiloscope which wasa transmitter-receiver system for detecting metallicobjects by means of electrical waves. The apparatus wasdesigned principally as an anticollision device for shipsand apparently did work quite successfully. In 1922,Marconi addressed the American Institute of ElectricalEngineers and suggested to his audience the possibility ofequipment that would be able to give warning of the pre-sence and bearing of ships in fog or darkness, eventhough these ships were not provided with any kind ofradio. Also in the USA in 1922, A.H. Taylor and L.C.Young, carrying out VHF propagation experiments at60 MHz, obtained reflections from buildings and awooden steamer. Experiments of G. Breit and T.A. Tuvein 1925 demonstrated the existence of a reflecting iono-spheric region in the upper atmosphere, and are invari-ably cited wherever the history of pulse radar isrecounted. Prior to this American work, Professor E.V.Appleton and M.A.F. Barnett of Britain had demon-strated the existence of a sky-reflected wave. In 1931,using 50 cm waves, W.A.S. Butement and P.E. Pollardcarried out successful experiments on the location ofships on the River Thames. L. Young and Hyland of theAmerican Naval Research Laboratory also carried outreflection experiments at distances up to 10 mile from thetransmitter; this occurrence laid the foundation of radarresearch in the USA, which rapidly expanded with theimmense scientific and industrial resources of thatcountry.
Just as television, whose technology is akin to radar inmany respects, became a working reality in the late1930s, so too did radar. It was assisted on its way inseveral countries by military needs but, like television, it
IEE PROCEEDINGS, Vol. 134, Pt. A, No. 4, APRIL 1987 349
would have emerged in any event and it is no surprise,therefore, that in three countries, Great Britain, the USAand Italy, the scientists intimately involved in its incep-tion had been active in studying radio-wave propagationand, in particular, with determining the height andnature of the ionosphere. Radar had to wait a time forthe necessary supporting technology such as reliablethermionic valves, cathode-ray tube displays and sensi-tive wideband receivers. The development of radar at thistime then owed much to talented practically orientedpeople, rather than theoreticians, who were competent inpractical radio electronics and who understood the meth-odology of radio-propagation measurements.
The urgency for the development of radar in Britain inthe mid-1930s arose because of the vulnerability of suchtargets as London to air attack, and the summer air exer-cises of 1934 had underlined the fact that Britain was vir-tually defenceless against air assault. Hence, theCommittee for the Scientific Survey of Air Defence, whichwas chaired by Sir Henry Tizard, encouraged researchand development of radiolocation as a means of givingwarning of the approach of aircraft. Prominent amongthe pioneering research workers were R. Watson Watt,A.F. Wilkins and E.G. Bowen. Chain home (CH) andchain home low (CHL) early warning radars, metric airborne radar (AI) and displays such as the plan positionindicator (PPI) were devised. On the production side,firms such as Metropolitan Vickers made transmitters,while Cossor concentrated on receivers. By the start ofhostilities in 1939, the East and South coasts of the UKwere well covered by CH and CHL radars, and werecrucial to the deployment of fighters in the 1940 summerBattle of Britain. In this, Britain had a more sophisti-cated air-defence organisation than Germany or Franceand, furthermore, there was, as radar developed, closeliaison between the scientists and the armed services, and,from the optimisation of the operation of the CH system,the science of operational research grew up, the namehaving been coined by A.P. Rowe, who played a key rolein the organisation of British radar throughout its devel-opment, and was the first Secretary of the Telecommuni-cations Research Establishment, Malvern (TRE nowRSRE).
In Germany, despite Hitler's directive prohibiting
research that did not produce more or less immediateresults, progress was also spectacular with the manufac-turers Gema, Telefunken, Siemens and Lorenz, producingwell engineered sets such as Freya and Wurzberg radarswhich were eventually made in large numbers.
R.M. Page played a major role in the development ofradar in the USA, and searchlight control radars, such asthe SCR 268 and related systems were extensively pro-duced by the Western Electric Company. In October1940, the Radiation Laboratory was set up at MIT andwas very fruitful in pioneering and developing many newradar systems for use by the Allies.
The effects of radar are numerous. It has changed thewhole conduct of warfare in the air, at sea and on land;its has contributed to safety in the air and at sea, and ithas also extended the science of measurement. Rug-gedness and reliability in electronic equipment owe muchto the severe demands placed on operational radarequipment in various theatres of war. On the theoreticalside, the study of threshold signals and noise and randomprocesses progressed as a matter of necessity. Automaticsearch, ranging and tracking radars promoted advancesin control electronics and control theory. Research onsilicon and germanium, carried out principally in theUSA, was boosted by the need for efficient crystal mixersfor radar receivers. Eventually, this led to the understand-ing of the controlled injection of impurities in semicon-ductors and, in 1948, to the invention of the transistor.The whole of modern microwave art and applicationstems from the development of radar. The offshootsinclude radio and radar astronomy, microwave commu-nications, microwave cooking, microwave spectroscopyof gases and paramagnetic materials, frequency standardsand masers.
Sean Swords is to be congratulated on collecting andlisting so much original material on the emergence ofradar worldwide, and for producing a most interestingand unbiased account of its early days. The book forms amost valuable addition to the IEE History of TechnologySeries.
G.R.WILKINSON
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