El Gigante is a huge letdown on return trip

In 1992, John Flenley, a specialist of palynology (the study of spores and pollens), and archaeologist Paul Bahn published Easter Island, Earth Island . The book advanced the thesis that a man-made ecological catastrophe must have taken place on Easter Island - that flyspeck in the middle of the Pacific between Tahiti and the coast of Chile - since it was once heavily forested but is now barren. Their latest book, The Enigmas of Easter Island , though with a different publisher, is a revision of Easter Island, Earth Island with minor amendments and with the doomsday warning to the rest of the planet in the conclusion toned down.

The more salient changes are updates to chapters on the ceremonial platforms ( ahu ) and on the giant stone statues ( moai ) that stood on the platforms and how they might have been moved, but the book still suffers from what marred the first version: too much must be taken on faith alone.

Sometimes the authors' explanations are incoherent. Thus in the chapter on the indigenous script known as rongorongo : "(Thomas) Barthel and other scholars reached the conclusion that the motifs represent a rudimentary phonetic writing system, in which picture symbols were used to express ideas as well as objects. In other words, the individual glyphs do not represent an alphabet or syllables." A "phonetic" writing system in which the signs do not represent phonemes or syllables but ideas and objects - that is novel.

Specious arguments are advanced by calling in specialist witnesses when needed and ignoring them when unwelcome. Thus, in that same chapter, to score a point against Thor Heyerdahl: "All current specialists, such as the Russians Butinov and Knorozov, say that the island's 'script' is clearly Polynesian." The reference is to a 1957 article in which Nikolai Butinov and Yuri Knorozov also wrote that the script was a mixture of the logographic and the phonetic, contra "Barthel and other scholars" - but there is no mention of that, nor that the pair identified a probable genealogy in one rongorongo tablet. The only interpretation of the rongorongo here is Steven Fischer's, which, applied to the genealogy discovered by Butinov and Knorozov, turns it into a tale of gods copulating with the same goddess to beget themselves. A veiled allusion is made to miscreants who reject Fischer's interpretation: "Inevitably it has failed to convince some other researchers who have fixed ideas of their own." No names, lest you might want to form your own opinion (the miscreants are Konstantin Pozdniakov and I).

One does not always need specialist knowledge, as in the rongorongo case, to smell a deception. The authors warn against trusting oral traditions: "All the recorded folk tales from the island need to be taken with a large pinch of sea salt." Yet they call in oral tradition as final arbiter when they argue against the moai statues having been toppled by an earthquake:

"There is absolutely no mention of such a recent and devastating catastrophe in the island's rich oral traditions: on the contrary, tales relate how, for example, the Tongariki statues were thrown down by an evil priest." Yet, 12 pages earlier they write that Ahu Tongariki was "destroyed to its foundations" by a tsunami in 1960. In his La Tierra de Hotu Matu'a , Father Sebastian Englert records that another ahu was destroyed by a tsunami in April 1946. Two ahu destroyed by tidal waves in less than 20 years; how many by evil priests?

Readers inclined to verify the authors' claims will find no supporting material here. There is no list of the ahu , no map showing their locations. William Thomson's report of his visit to Easter Island in 1886 included a long list. Englert enumerated 245 ahu , with location, description, state of disrepair. There were two detailed drawings of them in the 1992 edition, one showing a cross-section of a typical ahu , the other a bird's-eye view of an ahu and its ancillary structures: side wings, funerary cist and so on. Both have disappeared.

In fact, most of the original illustrations have disappeared. Easter Island, Earth Island had 20 full-page photographs. There are none here, and the photographs that are included or have replaced the originals are so poor that omitting them altogether would have been no loss. There is nothing recognisable in the photograph of El Gigante, "the biggest moai ever carved", even if you know what to look for, and in a colour photograph of the quarry where the statues were carved, "the giant heads poking up on the hillside" are a mere 1mm high.

This book is a guided tour of Easter Island similar to those of North Vietnam in the 1970s. You will learn only what the guides want you to know, and with most of the original artwork removed, you are now blindfolded.

There are no good recent books on Easter Island. There remains Catherine and Michel Orliac's treasure-trove of information, The Silent Gods: Mysteries of Easter Island . If you read French, Les Mystères Résolus de l'Ile de Pâques gives unbiased coverage. It even has two papers by Flenley.

Jacques B. M. Guy holds a PhD in linguistics from the Australian National University and is a specialist in the writing of Easter Island.