self-developing

SUBJECT AREA: Photography, film and optics

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Edwin Land's career began when, as a Harvard undergraduate in the late 1920s, he became interested in the possibility of developing a polarizing filter in the form of a thin sheet, to replace the crystal and stacked-glass devices then in use, which were expensive, cumbersome and limited in size. He succeeded in creating a material in which minute anisotropic iodine crystals were oriented in line, producing an efficient polarizer that was patented in 1929. After presenting the result of his researches in a Physics Department colloquium at Harvard, he left to form a partnership with George Wheelwright to manufacture the new material, which was seen to have applications as diverse as anti-glare car headlights, sunglasses, and viewing filters for stereoscopic photographs and films. In 1937 he founded the Polaroid Corporation and developed the Vectograph process, in which self-polarized photographic images could be printed, giving a stereoscopic image when viewed through polarizing viewers. Land's most significant invention, the instant picture, was stimulated by his three-year-old daughter. As he took a snapshot of her, she asked why she could not see the picture at once. He began to research the possibility, and on 21 February 1947 he demonstrated a system of one-step photography at a meeting of the Optical Society of America. Using the principle of diffusion transfer of the image, it produced a photograph in one minute. The Polaroid Land camera was launched on 26 November 1948. The original sepia-coloured images were soon replaced by black and white and, in 1963, by Polacolor instant colour film. The original peel-apart "wet" process was superseded in 1972 with the introduction of the SX-70 camera with dry picture units which developed in the light. The instant colour movie system Polavision, introduced in 1978, was less successful and was one of his few commercial failures.

Land died in March 1991, after a career in which he had been honoured by countless scien-tific and academic bodies and had received the Medal of Freedom, the highest civilian honour in America.

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SUBJECT AREA: Mechanical, pneumatic and hydraulic engineering

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James Nasmyth was the youngest son of Alexander Nasmyth (1758–1840), the portrait and landscape painter. According to his autobiography he was named James Hall after his father's friend, the geologist Sir James Hall (1761–1832), but he seems never to have used his second name in official documents. He received an elementary education at Edinburgh High School, but left at the age of 12. He attended evening classes at the Edinburgh School of Arts for the instruction of Mechanics between 1821 and 1825, and gained experience as a mechanic at an early age in his father's workshop. He shared these early experiences with his brother George, who was only a year or so older, and in the 1820s the brothers built several model steam engines and a steam-carriage capable of carrying eight passengers on the public roads. In 1829 Nasmyth obtained a position in London as personal assistant to Henry Maudslay, and after Maudslay's death in February 1831 he remained with Maudslay's partner, Joshua Field, for a short time. He then returned to Edinburgh, where he and his brother George started in a small way as general engineers. In 1834 they moved to a small workshop in Manchester, and in 1836, with the aid of financial backing from some Manchester businessmen, they established on a site at Patricroft, a few miles from the city, the works which became known as the Bridgewater Foundry. They were soon joined by a third partner, Holbrook Gaskell (1813–1909), who looked after the administration of the business, the firm then being known as Nasmyths Gaskell \& Co. They specialized in making machine tools, and Nasmyth invented many improvements so that they soon became one of the leading manufacturers in this field. They also made steam locomotives for the rapidly developing railways. James Nasmyth's best-known invention was the steam-hammer, which dates from 1839 but was not patented until 1842. The self-acting control gear was probably the work of Robert Wilson and ensured the commercial success of the invention. George Nasmyth resigned from the partnership in 1843 and in 1850 Gaskell also resigned, after which the firm continued as James Nasmyth \& Co. James Nasmyth himself retired at the end of 1856 and went to live at Penshurst, Kent, in a house which he named "Hammerfield" where he devoted his time mainly to his hobby of astronomy. Robert Wilson returned to become Managing Partner of the firm, which later became Nasmyth, Wilson \& Co. and retained that style until its closure in 1940. Nasmyth's claim to be the sole inventor of the steam-hammer has been disputed, but his patent of 1842 was not challenged and the fourteen-year monopoly ensured the prosperity of the business so that he was able to retire at the age of 48. At his death in 1890 he left an estate valued at £243,805.

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SUBJECT AREA: Mining and extraction technology

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The son of a mining officer, Oeynhausen started his career in the Prussian administration of the mining industry in 1816, immediately after he had finished his studies in natural sciences and mathematics at the University of Göttingen. From 1847 until his retirement he was a most effective head of state mines inspectorates, first in Silesia (Breslau; now Wroclaw, Poland), later in Westphalia (Dortmund). During his working life he served in all the important mining districts of Prussia, and travelled to mining areas in other parts of Germany, Belgium, France and Britain. In the 1820s, after visiting Glenck's well-known saltworks near Wimpfen, he was commissioned to search for salt deposits in Prussian territory, where he discovered the thermal springs south of Minden which later became the renowned spa carrying his name.

With deeper drills, the increased weight of the rods made it difficult to disengage the drill on each stroke and made the apparatus self-destructive on impact of the drill. Oeynhausen, from 1834, used fish joints, flexible connections between the drill and the rods. Not only did they prevent destructive impact, but they also gave a jerk on the return stroke that facilitated disengagements. He never claimed to have invented the fish joints: in fact, they appeared almost simultaneously in Europe and in America at that time, and had been used since at least the seventeenth century in China, although they were unknown in the Western hemisphere.

Using fish joints meant the start of a new era in deep-drilling, allowing much deeper wells to be sunk than before. Five weeks after Oeynhausen, K.G. Kind operated with a different kind of fish joint, and in 1845 another Prussian mining officer, Karl Leopold Fabian (1782–1855), Director of the salt inspectorate at Schönebeck, Elbe, improved the fish joints by developing a special device between the rod and the drill to enable the chisel, strengthened by a sinker bar, to fall onto the bottom of the hole without hindrance with a higher effect. The free-fall system became another factor in the outstanding results of deep-drilling in Prussia in the nineteenth century.

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SUBJECT AREA: Textiles

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The family firm of Paget's of Loughborough was of long standing in hosiery manufacture. They were well aware of the importance of modernizing their factory with the latest improvements in machinery, as well as developing their own inventions. They discovered Marc Brunel's circular knitting machine c.1844 and constructed many on that principle, with modifications that performed very well. Arthur Paget took out three patents. The first, was in 1857, was for making the machine self-acting so that it could be driven by power. In his patent of 1859 he introduced modifications on the earlier patent, and his third patent, in 1860, described further alterations. These machines produced excellent work with speed and accuracy.

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   1) The Qualities of a Mindful State of Being

   he key qualities of a mindful state of being [are]: (1) creation of new categories; (2) openness to new information; and (3) awareness of more than one perspective. (E. J. Langer, 1989, p. 62)

   2) Most Situations Can Become Subject to Control If Viewed Mindfully

   Even the most apparently fixed and certain situations can become subject to control if viewed mindfully. The Birdman of Alcatraz was sentenced to life in prison with no hope of reprieve. All the world was cut off from him; one empty, grim day followed the next, as he stared at the flocks of birds flying outside his window. One morning, a crippled sparrow happened into his cell, and he nursed it back to health. The bird was no longer just a bird; for him it was a particular sparrow. Other prisoners, guards, visitors started giving him birds and he learned more and more about them. Soon he had a veritable aviary in his cell. He became a distinguished authority on bird diseases, noticing more and more about these creatures and developing more and more expertise. Everything he did was self-taught and original.

   Instead of living a dull, stale existence in a cell for forty-odd years, the Birdman of Alcatraz found that boredom can be just another construct of the mind, no more certain than freedom. There is always something new to notice. And he turned what might have been an absolute hell into, at the least, a fascinating, mindful purgatory. (E. J. Langer, 1989, p. 74)