Workers tunnelling the Central line in 1898. Gelatin silver print
Any history of photography begins with William Henry Fox Talbot and Louis Daguerre, though the exhibition's focus on the former can probably be attributed to the weight of material available rather than Anglo one-upmanship. A hopeless painter, Talbot was keen to realise a device that could capture an image for posterity; he was familiar with the camera lucida, but his invention of the calotype process enabled him to fix the image for posterity using paper coated with silver iodide. The exhibition does well in mapping out why this process won out over the Daguerrotype, which despite it's silver nitrate brilliance and clarity of focus, had a fundamental flaw: each print was unique, and impossible to reproduce. By 1850, the quiddity of photography — its mechanical representation of reality and potential for unlimited reproduction — were well established.
The exhibition moves from the early experiments to the revolution it offered to science and industry, and the dubious boost it provided to new pursuits and disciplines such as anthropology and travel: Thomas Cook launched his first excursion in 1841, and there are plenty of photographs showing far-off lands and their inhabitants, the latter often posed, with the keen colonialist eye, to exaggerate their alien nature. The effect of this new and potentially troublesome invention on contemporary wits is profound: Baudelaire exalted its potential for science while bemoaning it as a "refuge for failed painters", while portraits of an uncomfortable-looking Charles Dickens are accompanied by his remarks in 1858 that he saw the "detestable lens pointing at me in the street [or] lurking in the bye-lanes". 150 years later, the likes of Amy Winehouse still make similar complaints.
The curators also make great use of the Library's collection of photographic technology through the decades, from an early camera lucida through to a portable processing tent that looks like a Bedouin lair full of potions and elixirs. Fox Talbot's description of photography was the 'Pen of Nature' seems ill-judged when faced with all this industrial expertise.
For the Londoner, the exhibition is particularly worthwhile for the images it shows of the city's 19th life: great projects of the Victorian age, like the building of Crystal Palace and Nelson's Column, and the tunnelling of the Central Line, are set against more mundane documentary fare, like the immobile hippo at London Zoo in 1984: a perfect subject for photography, as his lack of movement allowed the long exposure time necessary for a good image.
Points Of View, at the British Library, until March 7th 2010. Entry is free