Hylozoic/Desires: Salt Cosmologies, Somerset House and The Hedge of Halomancy, Tate Britain review - the power of white powder

The railways that we built in India may be well known, but I bet you’ve never heard of the Customs Line, a hedge that stretched 2,500 miles across the subcontinent all the way from the River Indus to the border between Madras and Bengal – the distance between London and Istanbul. Comparable in scale to the great Wall of China, this 40-foot high barrier was created to prevent the smuggling of salt.

Before the advent of refrigeration, salt played a crucial role in preserving food. Taxing a substance so essential for survival was a sure way of getting rich and the British East India Company was quick to capitalise on the idea. The levy they imposed gradually increased until it reached a preposterous 2,500 per cent, making it unaffordable for most Indians. Smuggling was, therefore, rife and the hedge was planted as a way of controlling the illegal trade.

The artist duo Hylozoic/Desires (Himali Singh Soin & David Soin Tappeser) were invited by Somerset House to recreate the lost archive of the Customs Line. How, though, to represent a vast hedge that has long since disappeared and been all but erased from memory as no photographs of it are to be found? Winding across the courtyard of Somerset House is a barrier created from lengths of organic cotton strung together in a line that echoes the shape of the monstrous hedge (main picture).

Printed with dyes obtained from plants like the cacti, prickly pear and thorny acacia, from which the hedge was constructed, are motifs referring to the plants and the birds that nested among them. On the reverse side are the stamps used to certify payment of the tax; these accumulate from one panel to the next until they form a dense mesh of deep crimson, the colour of the cochineal beetles that lived among the vegetation.

Somerset House was home to the Salt Office which controlled the production, shipping and taxation of salt nearer home, and this room now houses the recreated archive of India’s Customs Line. Over the mantelpiece is a map from 1874 showing the extent of the hedge, with samples of the plants used in its construction and the birds that nested helping to bring the plan to life.

Most intriguing is the role of Allan Octavian Hume who, as Commissioner of Customs, oversaw the collection of taxes and supervised the 12, 911 armed guards who manned the checkpoints dotted every 3-400 yards along the Line and the dacoits responsible for its upkeep. Lord Hume gradually became disenchanted with the Colonial Service and, in 1882, defected to the other side, helping to set up the Indian National Congress that would eventually achieve Independence. He was a keen botanist and ornithologist and many of the bird and plant specimens on show come from his collection.

Also included is the Deed of Trespass issued to Mahatma Ghandi, leader of the Indian National Congress when, in April 1930, he and some 2,000 followers marched to Sambhar Salt Lake in Rajasthan where much of the salt was produced and, in symbolic protest, helped himself to lumps of the precious mineral.

Missing from this fascinating display, though, is a sense of the artists’ presence. For that you need to descend the refurbished salt stairs accompanied by White Noise, whose crackling sounds were made with salt. Lining the walls are AI generated photographs; simulating Victorian salt prints, they create the impression that a photographer was on hand in the 1840s to record workers at the salt lake (pictured above right) and dacoits maintaining the hedge (pictured above). It’s like “reinserting them back into history” says Singh Soin. At the foot of the stairs is The Phantom Line, 2025 a video which, with the help of Google Earth, traces the path once followed by the Customs Line.

Meanwhile, showing at Tate Britain is The Hedge of Halomancy 2025, a video in which the history and symbolism of the hedge is explored through the fortunes of Mayalee, a courtesan (played by Himali Singh Soin) (pictured below) who defied the Raj’s attempts to cut the stipends she was paid in salt. Beautiful shots of the salt lake and the pink flamingoes that gather in their thousands are interspersed with information about the hedge and images of Mayalee using the salt for holomancy – divination. She sifts the substance through her fingers, hoping perhaps to alter the course of history by influencing Lord Hume through her prophecies.

This awkward mix of documentary and poetic imagination is not helped by the installation. To simulate the experience of gazing over the vast salt lake, the screen is placed on the floor. And to help you see the words appearing on it, the screen it is tilted up, but not enough to allow you to read them properly. Meanwhile, frenetic sitar music drowns out the voice-over, further compromising the message of a work that is already split between two venues.

• Salt Cosmologies is at Somerset House until 27 April, The Hedge of Halomancy is at Tate Britain until 28 August
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