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12.11.2010

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MACFARLANE, SIR DONALD HORNE
(1830–1904)

The son of a magistrate in Caithness, where he was born in July 1830, Macfarlane went to India in the late 1850s as a partner in the firm of Begg, Dunlop and Co., agents for tea and coal interests in the subcontinent. He appears to have taken up photography as an amateur soon after his arrival and the quality of his work attracted notice when he joined the Bengal Photographic Society in 1860. He remained an active and enthusiastic member of the society until his departure from India in 1864, win- ning numerous medals in its competitions and contrib- uting several papers to its journal. The most important of these, Landscape photography in India, appeared in September 1862 and from 1863–64 he served as the society’s president. Macfarlane’s landscape work, small in quantity in terms of known examples, nevertheless reflects one of the freshest and most individual responses to the Indian landscape in the early 1860s and displays a remarkably modern compositional approach. Although Macfarlane continued with photography on his return to Europe and had his work shown at the Paris Exhibi- tion of 1867, examples of this have not so far come to light: the scarcity of surviving prints has certainly led to an unwarranted neglect of one of the most individual photographic eyes in India in the 1860s. In his later years he served as Member of Parliament for Carlow (1880) and Argyllshire (1885, 1892), dying in London on 2 June 1904.

MACH, ERNST (1838–1916)
Moravian physicist

From early in the second half of the nineteenth century, photographers increasingly sought not just to decrease exposure times, but to shorten them sufficiently to be able to capture moving subjects with the crispness and full tonal range that was possible in a landscape view or a studio portrait. Gustav le Gray, Count Michael Ester- hazy, Albert Lugardon, Ottomar Anschütz, and others achieved international recognition through their ability to depict movements in “instantaneous” photographs that recorded the natural motion of their subjects. The most spectacular instantaneous photographs captured movements too fast to be seen by the human eye, such as bullets or cannon shells in flight, and melded advanced photographic technology with a specialised optical apparatus developed by the professor of physics in Bonn, Dr. August Toepler, at the end of the 1850s and published in 1864. Toepler was interested in observing variations in the density of gases and fluids, and devised an apparatus where an “experimental space” containing his transparent media was framed by two plano-convex lenses on opposite sides, whose focal point was then observed by a further pair of enlarging lenses. The experimental space was lit from behind, and precisely half of the rays of its lenses were blocked by a shutter just at their focal point, in front of the observing lenses. With this specialised setup, any variation in the refrac- tion of light passing through the experimental space caused by uneven density in the material showed up at the observation point as an unfocussed streak of light, and a Schlieren (“streak”) apparatus became a standard laboratory instrument, not only for work on fluids but also for checking the imperfections of optical lenses. When a camera replaced the human eye at the observa- tion point, and an electric spark provided appropriate illumination for a darkened experimental space, any fast-moving object that passed through the space, and the effects on the air caused by its movement, could be photographed, measured, and studied, given that a proper electrical circuit timed the release of the spark just as the object was passing through the experimental space or Schlieren Head.
Beginning in 1884 Ernst Mach began using the Schlieren Method to photograph bullets fired by a pis- tol, drawn into a controversy about whether or not the French had used illegal explosive bullets, outlawed in the Treaty of St. Petersburg of 1868, during the Franco- Prussian war of 1870–71. New French rifles had caused extreme, crater-like wounds, and throughout the 1870s a number of explanations for the phenomenon had been put forward, including an idea suggested by Louis Melsens of Belgium that a spherical projectile carried compressed air with it in flight, the amount depending on its velocity. In his first experiments Mach saw no significant turbulence in the air because the bullets were travelling too slowly; he asked his colleagues Peter Salcher and S. Riegler at the Marine Academy in Fiume to continue his experiments, and they modified another Schlieren apparatus to Mach’s specifications, photographing bullets fired from several types of rifles. In summer 1886 the shock waves from a bullet travelling faster than the speed of sound were photographed for the first time. Mach, assisted by his son Ludwig, then continued the experiments that autumn making more photographs of the air turbulence around a variety of projectiles, and even built a remarkable apparatus at the Krupp artillery range in Meppen where a 4 cm rapid- firing cannon was fired through a specially-built shed that provided the darkness needed to make a photograph where the plate was exposed by illumination from an electric spark. Mach began publishing his results with Salcher in 1887, and caused much excitement in both the scientific and photographic worlds. Ottomar Anschütz was inspired to make the only daylight photograph of a flying cannonshell in 1888, using specially designed weighted, pneumatically driven and electrically released focal plane shutters that operated at 76 millionths of a second at the Krupp Gruson works at Buckau- Magdeburg. Sir Charles Vernon Boys, who had made photographs of falling drops of water and other liquids by moving a photographic plate by hand through a camera while a slotted rotating disk shutter ran in front of his camera lens in the late 1880s, repeated Mach’s Schlieren-method work in 1891 and 1892, producing photographs of bullets piercing a sheet of glass and other materials. Unusually, Boys used no lens in his camera, relying instead on the nearness of the bullet to the plate and his own improvements in the design of the electrical release mechanism, which much improved the briefness of his spark, to produce a defined image. Helmut Gernsheim’s dismissive comment on the work of Mach and Boys, based on the fact that because the subjects were back-lit from behind the Schlieren Head the photographs produced only shadows of the passing object, seems today distinctly ungenerous. Their in-
novative technical expansion of the usefulness of pho- tography not only led to specific scientific discoveries, but also gave new impetus to the field of electric-spark photography pioneered by Prof. Bernhard Wilhelm Feddersen in the late 1850s, and ultimately led to the striking images of Harold Edgerton at MIT in the 1930s and the development of modern stroboscopic flash units both large and small.

Biography
Born at Turas, Moravia (today Czech Republic), Ernst Mach was educated at the University of Vienna, gaining his PhD in 1860. Four years later he was named profes- sor of mathematics at Graz, and next took the chair of physics at the University of Prague in 1867, where he remained for the next 28 years. At Prague, Mach con- centrated on experiments in psychology and perception, and worked on optics, mechanics and wave dynamics. He discovered the function of the semicircular canals of the ear; a phenomenon of the eye where it sees bright or dark bands near the boundaries between areas of starkly constrasting illumination, still called Mach’s Bands; and first described the shock waves in the air that precede an object travelling faster than the speed of sound, leading to the colloquial expression of “Mach I” or “Mach II” for the speed of military and experimental aircraft. This last discovery was made in a series of trials using advanced photographic methods. Parallel with his experimental work in the 1880s, Mach proposed that all knowledge is derived from physical sensations, and began to argue for a rigorous interpretation of science based only on the interpretation of verifiable empirical observation. He further developed a radical concept of inertia, which he considered was exclusively a function of the interac- tion between one body and all the other bodies in the universe, a view which was not only controversial but which was one of the inspirations for Einstein’s theory of relativity. His rejection of the existence of atoms, and his contention that matter was constructed wholly out of pure sensation was equally influential on the logical positivist philosophers, and embroiled him in vivid public disputes with Max Planck, Oswald Külpe, and even Vladimir Lenin. Mach’s scientific legacy is principally as a philosopher of science although he al- ways considered himself nothing other than a rigorous physicist. Moving to the University of Vienna in 1895, where he became professor of the history and theory of the inductive sciences, Mach began an intense battle against Einstein’s theory of relativity which dominated his later work, even though he was partially paralysed by a stroke in 1901. Widely influential on European physics practitioners during his lifetime, his fight with Einstein ultimately eclipsed his reputation until recently, when new theories about the properties and composi- tion of sub-atomic particles have revived interest in his concepts.

MACKEY, FATHER PETER PAUL (1851–1935)
English-born amateur photographer

Father Mackey epitomises the private photographer: a learned scholar who knew the relevance of what he was looking for and at; precise, as befits the “age of the tripod,” technically expert, poetic, he had a great love of architecture. A tireless walker, he made excursions throughout Italy, and to Sardinia and Greece, c.1884– 1902, and because he travelled off the souvenir routes, he photographed many places not covered by commercial photographers. His depictions of the nuraghe in Sardinia are the earliest in existence. Equally rare is his record of the natural life of the Italian countryside, a subject not recognised by the professionals. Rarer still is the way he portrays the world for it is seen through the eyes of a Dominican priest who should not have been so interested in transitory, worldly things; self-portraits depict him deep in poetic thought in his flowing habit amidst pagan, classical ruins. Born Erdington, Birmingham, Daniel Mackey studied law (1869–1871) then the priesthood at Woodchester where, after becoming a Lector in Sacred Theology at Louvain in 1874, he taught philosophy and canon law until summoned to Rome in 1881 as editor of the Leonine edition of the works of St Thomas Aqui- nas which he continued for the rest of his life. He also associated with artists, such as Rodin, art dealers and collectors. He presented his photographic albums to the British and American Archeological Society of Rome
(one remains). He gave to the British School at Rome c.1913 his negatives (now lost) and nearly 2000 prints, together with a detailed catalogue, which remained forgotten until 1999. They are now of great interest.

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