subject+at+university

SUBJECT AREA: Agricultural and food technology

[br]

[br]

[br]

John Augustus Voelcker, as the son of Dr John Christopher Voelcker, grew up in an atmosphere of scientific agriculture and would have had contact with the leading agriculturists of the day. He was educated at University College School and then University College, London, where he obtained both a BA and a BSc Following in his father's footsteps, he studied for his PhD at Giessen University in Germany. At college he enjoyed athletics, an interest he was to pursue for the rest of his life. He decided to take up agricultural chemistry and was to succeed to all the public offices once held by his father, from whom he also took over the directorship of Woburn Farm. The experimental farm had been started in 1876 and was used to study the residual effects of chemicals in the soil. The results of these studies were used as the basis for compensation awards to tenant farmers giving up their farms. Voelcker broadened the range of studies to include trace elements in the soil, but by 1921 the Royal Agricultural Society of England had decided to give up the farm. This was a blow to Voelcker and occurred just before experiments elsewhere highlighted the importance of these elements to healthy plant growth. He continued the research at his own expense until the Rothampsted Experimental Station took over the farm in 1926. Aside from his achievements in Britain, Voelcker undertook a study tour of India in 1890, the report on which led to the appointment of an Agricultural Chemist, and the establishment of a scientific service for the Indian subcontinent.

[br]

SUBJECT AREA: Photography, film and optics

[br]

[br]

[br]

After completing his early education in Weimar, Zeiss became an apprentice to the engineer Dr Frederick Koerner. As part of his training, Zeiss was required to travel widely and he visited Vienna, Berlin, Stuttgart and Darmstadt to study his trade. In 1846 he set up a business of his own, an optical workshop in Jena, where he began manufacturing magnifying glasses and microscopes. Much of his work was naturally for the university there and he had the co-operation of some of the University staff in the development of precision instruments. By 1858 he was seeking to make more expensive compound microscopes, but he found the current techniques primitive and laborious. He decided that it was necessary to introduce scientific method to the design of the optics, and in 1866 he sought the advice of a professor of physics at the University of Jena, Ernst Abbe (1840–1905). It took Zeiss until 1869 to persuade Abbe to join his company, and two difficult years were spent working on the calculations before success was achieved. Within a few more years the Zeiss microscope had earned a worldwide reputation for quality. Abbe became a full partner in the Zeiss business in 1875. In 1880 Abbe began an association with Friedrich Otte Schott that was to lead to the establishment of the famous Jena glass works in 1884. With the support of the German government, Jena was to become the centre of world production of new optical glasses for photographic objectives.

In 1886 the distinguished mathematician and optician Paul Rudolph joined Zeiss at Jena. After Zeiss's death, Rudolph went on to use the characteristics of the new glass to calculate the first anastigmatic lenses. Immediately successful and widely imitated, the anastigmats were also the first of a long series of Zeiss photographic objectives that were to be at the forefront of lens design for years to come. Abbe took over the management of the company and developed it into an internationally famous organization.

[br]

JW / RTS

SUBJECT AREA: Weapons and armour

[br]

[br]

[br]

Bothe studied under Max Planck at the University of Berlin, gaining his doctorate in 1914. After military service during the First World War, he resumed his investigations into nuclear physics and achieved a breakthrough in 1929 when he developed a method of studying cosmic radiation by placing one Geiger counter on top of another. From this he evolved the means of high-speed counting known as "coincidence counting". The following year, in conjunction with Hans Becker, Bothe made a Further stride forward when they identified a very penetrative neutral particle by bombarding beryllium with alpha particles; this was a significant advance towards creating nuclear energy in that the neutral particle was what Chadwick later identified as the neutron.

In 1934 Bothe's achievements were recognized by his appointment as Director of the Max Planck Institute for Medical Research, although this was after Planck himself had been deposed because of his Jewish sympathies. Bothe did, however, become primarily involved in Germany's pursuit of the atomic bomb and in 1944 constructed Germany's first cyclotron for accelerating nuclear particles. By that time Germany was faced with military defeat and Bothe was not able to develop his ideas further. Even so, for his work in the field of cosmic radiation Bothe shared the 1954 Nobel Prize for Physics with the naturalized Briton (formerly German) Max Born, whose subject was statistical mechanics.

[br]

SUBJECT AREA: Broadcasting, Electronics and information technology, Telecommunications

[br]

[br]

[br]

Kompfner obtained a degree in engineering from the Vienna Technische Hochschule in 1931 and qualified as a Diplom-Ingenieur in Architecture two years later. The following year, with a worsening political situation in Austria, he moved to England and became an architectural apprentice. In 1936 he became Managing Director of a building firm owned by a relative, but at the same time he was avidly studying physics and electronics. His first patent, for a television pick-up device, was filed in 1935 and granted in 1937, but was not in fact taken up. In June 1940 he was interned on the Isle of Man, but as a result of a paper previously sent by him to the Editor of Wireless Engineer he was released the following December and sent to join the group at Birmingham University working on centimetric radar. There he worked on klystrons, with little success, but as a result of the experience gained he eventually invented the travelling-wave tube (TWT), which was based on a helical transmission line. After disbandment of the Birmingham team, in 1946 Kompfner moved to the Clarendon Laboratory at Oxford and in 1947 he became a British subject. At the Clarendon Laboratory he met J.R. Pierce of Bell Laboratories, who worked out the theory of operation of the TWT. After gaining his DPhil at Oxford in 1951, Kompfner accepted a post as Principal Scientific Officer at Signals Electronic Research Laboratories, Baldock, but very soon after that he was invited by Pierce to work at Bell on microwave tubes. There, in 1952, he invented the backward-wave oscillator (BWO). He was appointed Director of Electronics Research in 1955 and Director of Communications Research in 1962, having become a US citizen in 1957. In 1958, with Pierce, he designed Echo 1, the first (passive) satellite, which was launched in August 1960. He was also involved with the development of Telstar, the first active communications satellite, which was launched in 1962. Following his retirement from Bell in 1973, he continued to pursue research, alternately at Stanford, California, and Oxford, England.

[br]

SUBJECT AREA: Photography, film and optics

[br]

[br]

[br]

Born of French parents, Lippman's work began with a distinguished career in classics, philosophy, mathematics and physics at the Ecole Normale in Luxembourg. After further studies in physics at Heidelberg University, he returned to France and the Sorbonne, where he was in 1886 appointed Director of Physics. He was a leading pioneer in France of research into electricity, optics, heat and other branches of physics.

In 1886 he conceived the idea of recording the existence of standing waves in light when it is reflected back on itself, by photographing the colours so produced. This required the production of a photographic emulsion that was effectively grainless: the individual silver halide crystals had to be smaller than the shortest wavelength of light to be recorded. Lippman succeeded in this and in 1891 demonstrated his process. A glass plate was coated with a grainless emulsion and held in a special plate-holder, glass towards the lens. The back of the holder was filled with mercury, which provided a perfect reflector when in contact with the emulsion. The standing waves produced during the exposure formed laminae in the emulsion, with the number of laminae being determined by the wavelength of the incoming light at each point on the image. When the processed plate was viewed under the correct lighting conditions, a theoretically exact reproduction of the colours of the original subject could be seen. However, the Lippman process remained a beautiful scientific demonstration only, since the ultra-fine-grain emulsion was very slow, requiring exposure times of over 10,000 times that of conventional negative material. Any method of increasing the speed of the emulsion also increased the grain size and destroyed the conditions required for the process to work.

[br]

SUBJECT AREA: Aerospace, Weapons and armour

[br]

[br]

[br]

Maxim was born the son of a pioneer farmer who later became a wood turner. Young Maxim was first apprenticed to a carriage maker and then embarked on a succession of jobs before joining his uncle in his engineering firm in Massachusetts in 1864. As a young man he gained a reputation as a boxer, but it was his uncle who first identified and encouraged Hiram's latent talent for invention.

It was not, however, until 1878, when Maxim joined the first electric-light company to be established in the USA, as its Chief Engineer, that he began to make a name for himself. He developed an improved light filament and his electric pressure regulator not only won a prize at the first International Electrical Exhibition, held in Paris in 1881, but also resulted in his being made a Chevalier de la Légion d'honneur. While in Europe he was advised that weapons development was a more lucrative field than electricity; consequently, he moved to England and established a small laboratory at Hatton Garden, London. He began by investigating improvements to the Gatling gun in order to produce a weapon with a faster rate of fire and which was more accurate. In 1883, by adapting a Winchester carbine, he successfully produced a semi-automatic weapon, which used the recoil to cock the gun automatically after firing. The following year he took this concept a stage further and produced a fully automatic belt-fed weapon. The recoil drove barrel and breechblock to the vent. The barrel then halted, while the breechblock, now unlocked from the former, continued rearwards, extracting the spent case and recocking the firing mechanism. The return spring, which it had been compressing, then drove the breechblock forward again, chambering the next round, which had been fed from the belt, as it did so. Keeping the trigger pressed enabled the gun to continue firing until the belt was expended. The Maxim gun, as it became known, was adopted by almost every army within the decade, and was to remain in service for nearly fifty years. Maxim himself joined forces with the large British armaments firm of Vickers, and the Vickers machine gun, which served the British Army during two world wars, was merely a refined version of the Maxim gun.

Maxim's interests continued to occupy several fields of technology, including flight. In 1891 he took out a patent for a steam-powered aeroplane fitted with a pendulous gyroscopic stabilizer which would maintain the pitch of the aeroplane at any desired inclination (basically, a simple autopilot). Maxim decided to test the relationship between power, thrust and lift before moving on to stability and control. He designed a lightweight steam-engine which developed 180 hp (135 kW) and drove a propeller measuring 17 ft 10 in. (5.44 m) in diameter. He fitted two of these engines into his huge flying machine testrig, which needed a wing span of 104 ft (31.7 m) to generate enough lift to overcome a total weight of 4 tons. The machine was not designed for free flight, but ran on one set of rails with a second set to prevent it rising more than about 2 ft (61 cm). At Baldwyn's Park in Kent on 31 July 1894 the huge machine, carrying Maxim and his crew, reached a speed of 42 mph (67.6 km/h) and lifted off its rails. Unfortunately, one of the restraining axles broke and the machine was extensively damaged. Although it was subsequently repaired and further trials carried out, these experiments were very expensive. Maxim eventually abandoned the flying machine and did not develop his idea for a stabilizer, turning instead to other projects. At the age of almost 70 he returned to the problems of flight and designed a biplane with a petrol engine: it was built in 1910 but never left the ground.

In all, Maxim registered 122 US and 149 British patents on objects ranging from mousetraps to automatic spindles. Included among them was a 1901 patent for a foot-operated suction cleaner. In 1900 he became a British subject and he was knighted the following year. He remained a larger-than-life figure, both physically and in character, until the end of his life.

[br]

See also: Pilcher, Percy Sinclair

CM / JDS

SUBJECT AREA: Ports and shipping

[br]

[br]

[br]

McNeill was born in Clydebank just outside Glasgow, and was to serve that town for most of his life. After education at Clydebank High School and then at Allan Glen's in Glasgow, in 1908 he entered the shipyard of John Brown \& Co. Ltd as an apprentice. He was encouraged to matriculate at the University of Glasgow, where he studied naval architecture under the (then) unique Glasgow system of "sandwich" training, alternately spending six months in the shipyard, followed by winter at the Faculty of Engineering. On graduating in 1915, he joined the Army and by 1918 had risen to the rank of Major in the Royal Field Artillery.

After the First World War, McNeill returned to the shipyard and in 1928 was appointed Chief Naval Architect. In 1934 he was made a local director of the company. During the difficult period of the 1930s he was in charge of the technical work which led to the design, launching and successful completion of the great liners Queen Mary and Queen Elizabeth. Some of the most remarkable ships of the mid-twentieth century were to come from this shipyard, including the last British battleship, HMS Vanguard, and the Royal Yacht Britannia, completed in 1954. From 1948 until 1959, Sir James was Managing Director of the Clydebank part of the company and was Deputy Chairman by the time he retired in 1962. His public service was remarkable and included chairmanship of the Shipbuilding Conference and of the British Ship Research Association, and membership of the Committee of Lloyd's Register of Shipping.

[br]

SUBJECT AREA: Metallurgy

[br]

[br]

[br]

Born into a Quaker family, he was educated at private schools; his studies included electricity and chemistry, with a bias towards metallurgy. Around 1821 Pattinson became Clerk and Assistant to Anthony Clapham, a soap-boiler of Newcastle upon Tyne. In 1825 he secured appointment as Assay Master to the lords of the manor of Alston. There he was able to pursue the subject of special interest to him, and in January 1829 he devised a method of separating silver from lead ore; however, he was prevented from developing it because of a lack of funds.

Two years later he was appointed Manager of Wentworth Beaumont's lead-works. There he was able to continue his researches, which culminated in the patent of 1833 enshrining the invention by which he is best known: a new process for extracting silver from lead by skimming crystals of pure lead with a perforated ladle from the surface of the molten silver-bearing lead, contained in a succession of cast-iron pots. The molten metal was stirred as it cooled until one pot provided a metal containing 300 oz. of silver to the ton (8,370 g to the tonne). Until that time, it was unprofitable to extract silver from lead ores containing less than 8 oz. per ton (223 g per tonne), but the Pattinson process reduced that to 2–3 oz. (56–84 g per tonne), and it therefore won wide acceptance. Pattinson resigned his post and went into partnership to establish a chemical works near Gateshead. He was able to devise two further processes of importance, one an improved method of obtaining white lead and the other a new process for manufacturing magnesia alba, or basic carbonate of magnesium. Both processes were patented in 1841.

Pattinson retired in 1858 and devoted himself to the study of astronomy, aided by a 7½ in. (19 cm) equatorial telescope that he had erected at his home at Scot's House.

[br]

SUBJECT AREA: Mechanical, pneumatic and hydraulic engineering

[br]

[br]

[br]

Hans Renold was educated at the cantonal school of his native town and at the Polytechnic in Zurich. He worked in two or three small workshops during the polytechnic vacations and served an apprenticeship of eighteen months in an engineering works at Neuchâtel, Switzerland. After a short period of military service he found employment as a draughtsman in an engineering firm at Saint-Denis, near Paris, from 1871 to 1873. In 1873 Renold moved first to London and then to Manchester as a draughtsman and inspector with a firm of machinery exporters. From 1877 to 1879 he was a partner in his own firm of machine exporters. In 1879 he purchased a small firm in Salford making chain for the textile industry. At about this time J.K.Starley introduced the "safety" bicycle, which, however, lacked a satisfactory drive chain. Renold met this need with the invention of the bush roller chain, which he patented in 1880. The new chain formed the basis of the precision chain industry: the business expanded and new premises were acquired in Brook Street, Manchester, in 1881. In the same year Renold became a naturalized British subject.

Continued expansion of the business necessitated the opening of a new factory in Brook Street in 1889. The factory was extended in 1895, but by 1906 more accommodation was needed and a site of 11 ½ acres was acquired in the Manchester suburb of Burnage: the move to the new building was finally completed in 1914. Over the years, further developments in the techniques of chain manufacture were made, including the invention in 1895 of the inverted tooth or silent chain. Renold made his first visit to America in 1891 to study machine-tool developments and designed for his own works special machine tools, including centreless grinding machines for dealing with wire rods up to 10 ft (3 m) in length.

The business was established as a private limited company in 1903 and merged with the Coventry Chain Company Ltd in 1930. Good industrial relations were always of concern to Renold and he established a 48-hour week as early as 1896, in which year a works canteen was opened. Joint consultation with shop stewards date2 from 1917. Renold was elected a Member of the Institution of Mechanical Engineers in 1902 and in 1917 he was made a magistrate of the City of Manchester.

[br]

SUBJECT AREA: Chemical technology

[br]

[br]

[br]

It was intended that Weldon should enter his father's factory in Loughborough, but he decided instead to turn to journalism, which he pursued with varying success in London. His Weldon's Register of Facts and Occurrences in Literature, Science, and Art ran for only four years, from 1860 to 1864, but the fashion magazine Weldon's Journal, which he published with his wife, was more successful. Meanwhile Weldon formed an interest in chemistry, although he had no formal training in that subject. He devoted himself to solving one of the great problems of industrial chemistry at that time. The Leblanc process for the manufacture of soda produced large quantities of hydrochloric acid in gas form. By this time, this by-product was being converted, by oxidation with manganese dioxide, to chlorine, which was much used in the textile and paper industries as a bleaching agent. The manganese ended up as manganese chloride, from which it was difficult to convert back to the oxide, for reuse in treating the hydrochloric acid, and it was an expensive substance. Weldon visited the St Helens district of Lancashire, an important centre for the manufacture of soda, to work on the problem. During the three years from 1866 to 1869, he took out six patents for the regeneration of manganese dioxide by treating the manganese chloride with milk of lime and blowing air through it. The Weldon process was quickly adopted and had a notable economic effect: the price of bleaching powder came down by £6 per ton and production went up fourfold.

By the time of his death, nearly all chlorine works in the world used Weldon's process. The distinguished French chemist J.B.A.Dumas said of the process, when presenting Weldon with a gold medal, "every sheet of paper and every yard of calico has been cheapened throughout the world". Weldon played an active part in the founding of the Society of Chemical Industry.

[br]

SUBJECT AREA: Automotive engineering, Land transport

[br]

[br]

[br]

Ackermann's father was a coachbuilder and harness-maker who in 1775 moved to Schneeberg. Rudolph was educated there and later entered his father's workshop for a short time. He visited Dresden, among other towns in Germany, and was resident in Paris for a short time, but eventually settled in London. For the first ten years of his life there he was employed in making designs for many of the leading coach builders. His steering-gear consisted of an arrangement of the track arms on the stub axles and their connection by the track rod in such a way that the inner wheel moved through a greater angle than the outer one, so giving approximately true rolling of the wheels in cornering. A necessary condition for this is that, in the plan view, the point of intersection of the axes of all the wheels must be at a point which always lies on the projection of the rear axle. In addition, the front wheels are inclined to bring the line of contact of the front wheels under the line of the pivots, about which they turn when cornering. This mechanism was not entirely new, having been proposed for windmill carriages in 1714 by Du Quet, but it was brought into prominence by Ackermann and so has come to bear his name.

In 1801 he patented a method of rendering paper, cloth and other materials waterproof and set up a factory in Chelsea for that purpose. He was one of the first private persons to light his business premises with gas. He also devoted some time to a patent for movable carriage axles between 1818 and 1820. In 1805 he was put in charge of the preparation of the funeral car for Lord Nelson.

Most of his life and endeavours were devoted to fine-art printing and publishing. He was responsible for the introduction into England of lithography as a fine art: it had first been introduced as a mechanical process in 1801, but was mainly used for copying until Ackermann took it up in 1817, setting up a press and engaging the services of a number of prominent artists, including W.H.Pyne, W.Combe, Pugin and Thomas Rowlandson. In 1819 he published an English translation of J.A.Senefelder's A Complete Course of Lithography, illustrated with lithographic plates from his press. He was much involved in charitable works for widows, children and wounded soldiers after the war of 1814. In 1830 he suffered "an attack of paralysis" which left him unable to continue in business. He died four years later and was buried at St Clement Danes.

[br]

SUBJECT AREA: Mechanical, pneumatic and hydraulic engineering, Metallurgy, Steam and internal combustion engines

[br]

[br]

[br]

Adamson was apprenticed between 1835 and 1841 to Timothy Hackworth, then Locomotive Superintendent on the Stockton \& Darlington Railway. After this he was appointed Draughtsman, then Superintendent Engineer, at that railway's locomotive works until in 1847 he became Manager of Shildon Works. In 1850 he resigned and moved to act as General Manager of Heaton Foundry, Stockport. In the following year he commenced business on his own at Newton Moor Iron Works near Manchester, where he built up his business as an iron-founder and boilermaker. By 1872 this works had become too small and he moved to a 4 acre (1.6 hectare) site at Hyde Junction, Dukinfield. There he employed 600 men making steel boilers, heavy machinery including mill engines fitted with the American Wheelock valve gear, hydraulic plant and general millwrighting. His success was based on his early recognition of the importance of using high-pressure steam and steel instead of wrought iron. In 1852 he patented his type of flanged seam for the firetubes of Lancashire boilers, which prevented these tubes cracking through expansion. In 1862 he patented the fabrication of boilers by drilling rivet holes instead of punching them and also by drilling the holes through two plates held together in their assembly positions. He had started to use steel for some boilers he made for railway locomotives in 1857, and in 1860, only four years after Bessemer's patent, he built six mill engine boilers from steel for Platt Bros, Oldham. He solved the problems of using this new material, and by his death had made c.2,800 steel boilers with pressures up to 250 psi (17.6 kg/cm²).

He was a pioneer in the general introduction of steel and in 1863–4 was a partner in establishing the Yorkshire Iron and Steel Works at Penistone. This was the first works to depend entirely upon Bessemer steel for engineering purposes and was later sold at a large profit to Charles Cammell \& Co., Sheffield. When he started this works, he also patented improvements both to the Bessemer converters and to the engines which provided their blast. In 1870 he helped to turn Lincolnshire into an important ironmaking area by erecting the North Lincolnshire Ironworks. He was also a shareholder in ironworks in South Wales and Cumberland.

He contributed to the development of the stationary steam engine, for as early as 1855 he built one to run with a pressure of 150 psi (10.5 kg/cm) that worked quite satisfactorily. He reheated the steam between the cylinders of compound engines and then in 1861–2 patented a triple-expansion engine, followed in 1873 by a quadruple-expansion one to further economize steam. In 1858 he developed improved machinery for testing tensile strength and compressive resistance of materials, and in the same year patents for hydraulic lifting jacks and riveting machines were obtained.

He was a founding member of the Iron and Steel Institute and became its President in 1888 when it visited Manchester. The previous year he had been President of the Institution of Civil Engineers when he was presented with the Bessemer Gold Medal. He was a constant contributor at the meetings of these associations as well as those of the Institution of Mechanical Engineers. He did not live to see the opening of one of his final achievements, the Manchester Ship Canal. He was the one man who, by his indomitable energy and skill at public speaking, roused the enthusiasm of the people in Manchester for this project and he made it a really practical proposition in the face of strong opposition.

[br]

SUBJECT AREA: Broadcasting, Electricity, Electronics and information technology, Telecommunications

[br]

[br]

[br]

After education in Sweden at the High School and University of Lund and the Royal Institution of Technology in Stockholm, Alexanderson took a postgraduate course at the Berlin-Charlottenburg Engineering College. In 1901 he began work for the Swedish C \& C Electric Company, joining the General Electric Company, Schenectady, New York, the following year. There, in 1906, together with Fessenden, he developed a series of high-power, high-frequency alternators, which had a dramatic effect on radio communications and resulted in the first real radio broadcast. His early interest in television led to working demonstrations in his own home in 1925 and at the General Electric laboratories in 1927, and to the first public demonstration of large-screen (7 ft (2.13 m) diagonal) projection TV in 1930. Another invention of significance was the "amplidyne", a sensitive manufacturing-control system subsequently used during the Second World War for controlling anti-aircraft guns. He also contributed to developments in electric propulsion and radio aerials.

He retired from General Electric in 1948, but continued television research as a consultant for the Radio Corporation of America (RCA), filing his 321st patent in 1955.

[br]

SUBJECT AREA: Broadcasting, Telecommunications

[br]

[br]

[br]

After early ambitions to become a professional cricketer, Appleton went to St John's College, Cambridge, where he studied under J.J.Thompson and Ernest Rutherford. His academic career interrupted by the First World War, he served as a captain in the Royal Engineers, carrying out investigations into the propagation and fading of radio signals. After the war he joined the Cavendish Laboratory, Cambridge, as a demonstrator in 1920, and in 1924 he moved to King's College, London, as Wheatstone Professor of Physics.

In the following decade he contributed to developments in valve oscillators (in particular, the "squegging" oscillator, which formed the basis of the first hard-valve time-base) and gained international recognition for research into electromagnetic-wave propagation. His most important contribution was to confirm the existence of a conducting ionospheric layer in the upper atmosphere capable of reflecting radio waves, which had been predicted almost simultaneously by Heaviside and Kennelly in 1902. This he did by persuading the BBC in 1924 to vary the frequency of their Bournemouth transmitter, and he then measured the signal received at Cambridge. By comparing the direct and reflected rays and the daily variation he was able to deduce that the Kennelly- Heaviside (the so-called E-layer) was at a height of about 60 miles (97 km) above the earth and that there was a further layer (the Appleton or F-layer) at about 150 miles (240 km), the latter being an efficient reflector of the shorter radio waves that penetrated the lower layers. During the period 1927–32 and aided by Hartree, he established a magneto-ionic theory to explain the existence of the ionosphere. He was instrumental in obtaining agreement for international co-operation for ionospheric and other measurements in the form of the Second Polar Year (1932–3) and, much later, the International Geophysical Year (1957–8). For all this work, which made it possible to forecast the optimum frequencies for long-distance short-wave communication as a function of the location of transmitter and receiver and of the time of day and year, in 1947 he was awarded the Nobel Prize for Physics.

He returned to Cambridge as Jacksonian Professor of Natural Philosophy in 1939, and with M.F. Barnett he investigated the possible use of radio waves for radio-location of aircraft. In 1939 he became Secretary of the Government Department of Scientific and Industrial Research, a post he held for ten years. During the Second World War he contributed to the development of both radar and the atomic bomb, and subsequently served on government committees concerned with the use of atomic energy (which led to the establishment of Harwell) and with scientific staff.

[br]

SUBJECT AREA: Broadcasting, Electronics and information technology, Telecommunications

[br]

[br]

[br]

Interested from childhood in anything mechanical, as a teenager Armstrong constructed a variety of wireless equipment in the attic of his parents' home, including spark-gap transmitters and receivers with iron-filing "coherer" detectors capable of producing weak Morse-code signals. In 1912, while still a student of engineering at Columbia University, he applied positive, i.e. regenerative, feedback to a Lee De Forest triode amplifier to just below the point of oscillation and obtained a gain of some 1,000 times, giving a receiver sensitivity very much greater than hitherto possible. Furthermore, by allowing the circuit to go into full oscillation he found he could generate stable continuous-waves, making possible the first reliable CW radio transmitter. Sadly, his claim to priority with this invention, for which he filed US patents in 1913, the year he graduated from Columbia, led to many years of litigation with De Forest, to whom the US Supreme Court finally, but unjustly, awarded the patent in 1934. The engineering world clearly did not agree with this decision, for the Institution of Radio Engineers did not revoke its previous award of a gold medal and he subsequently received the highest US scientific award, the Franklin Medal, for this discovery.

During the First World War, after some time as an instructor at Columbia University, he joined the US Signal Corps laboratories in Paris, where in 1918 he invented the superheterodyne, a major contribution to radio-receiver design and for which he filed a patent in 1920. The principle of this circuit, which underlies virtually all modern radio, TV and radar reception, is that by using a local oscillator to convert, or "heterodyne", a wanted signal to a lower, fixed, "intermediate" frequency it is possible to obtain high amplification and selectivity without the need to "track" the tuning of numerous variable circuits.

Returning to Columbia after the war and eventually becoming Professor of Electrical Engineering, he made a fortune from the sale of his patent rights and used part of his wealth to fund his own research into further problems in radio communication, particularly that of receiver noise. In 1933 he filed four patents covering the use of wide-band frequency modulation (FM) to achieve low-noise, high-fidelity sound broadcasting, but unable to interest RCA he eventually built a complete broadcast transmitter at his own expense in 1939 to prove the advantages of his system. Unfortunately, there followed another long battle to protect and exploit his patents, and exhausted and virtually ruined he took his own life in 1954, just as the use of FM became an established technique.

[br]

SUBJECT AREA: Civil engineering

[br]

[br]

[br]

Bailey was educated at the Leys School, Cambridge, before going to Sheffield University where he studied for a degree in engineering. He joined the Civil Service in 1928 and was posted to the staff of the Experimental Bridging Establishment of the Ministry of Supply at Christchurch, Hampshire. There he continued his boyhood hobby of making model bridges of wood and string. He evolved a design for a prefabricated metal bridge assembled from welded panels linked by pinned joints; this became known as the Bailey bridge. Its design was accepted by the War Office in 1941 and from then on it was used throughout the subsequent conflict of the Second World War. It was a great improvement on its predecessor, the Inglis bridge, designed by a Cambridge University professor of engineering, Charles Inglis, with tubular members that were 10 or 12 ft (3.66 m) long; this bridge was notoriously difficult to construct, particularly in adverse weather conditions, whereas the Bailey bridge's panels and joints were far more manageable and easy to assemble. The simple and standardized component parts of the Bailey bridge made it highly adaptable: it could be strengthened by increasing the number of truss girders, and wide rivers could be crossed by a series of Bailey bridges connected by pontoons. Field Marshal Montgomery is recorded as saying that without the Bailey bridge we should not have won the war'.

[br]

SUBJECT AREA: Agricultural and food technology

[br]

[br]

[br]

The son of a Forfarshire tenant farmer, Patrick Bell obtained an MA from the University of St Andrews. His early association with farming kindled an interest in engineering and mechanics and he was to maintain a workshop not only on his father's farm, but also, in later life, at the parsonage at Carmyllie.

He was still studying divinity when he invented his reaping machine. Using garden shears as the basis of his design, he built a model in 1827 and a full-scale prototype the following year. Not wishing the machine to be seen during his early experiments, he and his brother planted a sheaf of oats in soil laid out in a shed, and first tried the machine on this. It cut well enough but left the straw in a mess behind it. A canvas belt system was devised and another secret trial in the barn was followed by a night excursion into a field, where corn was successfully harvested.

Two machines were at work during 1828, apparently achieving a harvest rate of one acre per hour. In 1832 there were ten machines at work, and at least another four had been sent to the United States by this time. Despite their success Bell did not patent his design, feeling that the idea should be given free to the world. In later years he was to regret the decision, feeling that the many badly-made imitations resulted in its poor reputation and prevented its adoption.

Bell's calling took precedence over his inventive interests and after qualifying he went to Canada in 1833, spending four years in Fergus, Ontario. He later returned to Scotland and be-came the minister at Carmyllie, with a living of £150 per annum.

[br]

SUBJECT AREA: Chemical technology, Mining and extraction technology

[br]

[br]

[br]

Bissell first pursued a career in education, as Professor of Languages at the University of Norwich, Vermont, and then as Superintendent of Schools in New Orleans. After dabbling in journalism, he turned to law and was admitted to the Bar in New York City in 1853. The following year he was deeply impressed by the picture of a derrick on the label on a bottle of brine from Samuel M.Kier's brine well. Bissell saw in it a new possibility of producing petroleum and, with Jonathan G.Elveleth, formed the world's first oil company, the Pennsylvania Rock Oil Company, on 30 December 1854. The Company obtained a sample of oil at Hibbard Farm, Titusville, Pennsylvania, and sent it for examination to Benjamin Silliman Jr, Professor of Chemistry at Yale University. He reported on 16 April 1855 that by simple means nearly all the oil could be converted into useful substances. Bissell acted on this and began drilling near Oil Creek, Pennsylvania. On 27 August 1859 his contractor struck oil at 60 ft (18 m). This date is usually taken as the starting point of the modern oil industry, even though oil had been obtained two years earlier in Europe by drilling near Hannover and at Ploesti in Romania. Bissell returned to New York in 1863 and spent the rest of his life promoting enterprises connected with the oil industry.

[br]

SUBJECT AREA: Steam and internal combustion engines

[br]

[br]

[br]

Branca practised architecture at Loretto. In 1629 he published Le Machine: volume nuovo et di molto artificio, in which he described various mechanisms. One was the application of rolls for working copper, lead or the precious metals gold and silver. The rolls were powered by a form of smokejack with the gases from the fire passing up a long tube forming a chimney which, through gearing, turned the rolls. Another device used a jet of steam from a boiler issuing from a mouthpiece shaped like the head of a person to impinge upon blades around the circumference of a horizontal wheel, connected through triple reduction gearing to drop stamps, for pounding drugs. This was a form of impulse turbine and has been claimed as the first machine worked by steam to do a particular operation since Heron's temple doors.

[br]

SUBJECT AREA: Broadcasting, Electronics and information technology, Telecommunications

[br]

[br]

[br]

Branly received his education at the Lycée de Saint Quentin in the Département de l'Aisne and at the Henri IV College of Paris University, where he became a Fellow of the University, graduating as a Doctor of Physics in 1873. That year he was appointed a professor at the College of Bourges and Director of Physics Instruction at the Sorbonne. Three years later he moved to the Free School in Paris as Professor of Advanced Studies. In addition to these responsibilities, he qualified as an MD in 1882 and practised medicine from 1896 to 1916. Whilst carrying out experiments with Hertzian (radio) waves in 1890, Branly discovered that a tube of iron filings connected to a source of direct voltage only became conductive when the radio waves were present. This early form of rectifier, which he called a coherer and which needed regular tapping to maintain its response, was used to operate a relay when the waves were turned on and off by Morse signals, thus providing the first practical radio communication.

[br]

See also: Hertz, Heinrich Rudolph; Marconi, Marchese Guglielmo