I spent my formative years living by the beach, so the idea of being able to swim unhindered by lungs that need air to absorb oxygen was a fantastical one. Yes, I daydreamed about being a mermaid.

And, a few years ago, I discovered that mermaids were more than just an object of my imagination, or of myth and fairytale: they were real. Well, at least they were in the form of compound constructions for curiosity cabinets and travelling sideshows...

There are two types of 'mermaids' in natural history: the monkey fish and the 'jenny haniver':

As the name suggests, the monkey fish is comprised of the head and torso of a monkey (carved out of wood) and the tail of a fish, often with additional papier-mâché elements plus wood and wire for structure and support. The jenny haniver is constructed from a guitar fish (part of the Rhinobatidae family of rays) and has been fashioned since at least the 16th century, initially in the image of the lethal basilisk before (by way of dragon, devil and angel) taking on a more human form and being presented as a mermaid.

The mermaid of myth and legend, as depicted by painter John William Waterhouse (left), and mermaids of "reality", aka monkey fish, belonging to the British Museum (top right, © The Trustees of the British Museum) and the Horniman Museum (bottom right).

Ollie Crimmen, the Museum's fish curator, who also has a bit of a soft spot for mermaids, says it's a shame we don't have a monkey fish at the Museum, but was keen to discuss with me the two jenny hanivers held in our stores:

I think when people look at these things with modern eyes they think "how can people believe it?"

 

[But, in centuries past] when somebody went over the horizon in a ship they were more out of touch than astronauts are today. When they came back, if they came back, there was a huge expectation: "you must have seen something fantastic, you must have brought something back". There was a pressure to have seen marvellous things. It might sound mad to us, but it was the sheer pressure of the expectation of what you've seen once you'd gone over the horizon.

And those who had not been on the journey, who had not seen fantastic, foreign things, were willing to believe whatever was presented to them as fact. For how could they know any different without having ever seen it in the flesh themselves? Remember my mention in a previous blog about the 'legless bird of paradise'?

On the other hand, nature does come up with some very real, very strange creatures. Consider the platypus: when it was discovered in the 18th century many scientists had difficulty believing that its mix of reptilian and mammalian features could be genuine.

The Museum has one quite big jenny haniver which measures 54cm in height, and another 'more quaint, smaller one' that's much older, Ollie says. He's not sure of their origin, but suggests that Museum scientist Peter Dance 'maybe had a go' at making one.

The suggestion is not completely off the mark. In his book Animal Fakes and Frauds, Dance describes buying a jenny haniver in London's Soho around the 1960s or 70s. Perhaps this is the specimen now in our collection.

When I first began gathering material for this book, I found that jenny hanivers were still being made. I bought one in London. According to the proprietor of the shop in Soho, whence I obtained it, it was said to have come from the Gulf of Mexico. It was, he said, a very good selling line, and I know it did not take him long to sell the others he had.

The Museum's large jenny haniver specimen, front (left) and back (right). It measures 54cm tall and 29cm across.

There is no definitive answer as to where the name jenny haniver originates, although many cite 'Anvers' (the French name for Antwerp), as a source, as it was on the coasts of Belgium and Holland that these mermaids were said to have been caught.

Dance's book also includes a passage from Australian ichthyologist Gilbert P Whitley describing how jenny hanivers are made:

...[by] taking a small dead ray, curling its side fins over its back, and twisting its tail into any required position, a piece of string is tied round the head behind the jaws to form a neck and the ray is dried in the sun. During the subsequent shrinkage, the jaws project to form a snout and a hitherto concealed arch of cartilage protrudes so as to resemble folded arms. The nostrils, situated a little above the jaws, are transformed into a pair of eyes, the olfactory laminae resembling eyelashes. The result of this simple process, preserved with a coat of varnish and perhaps ornamented with a few dabs of paint, is a jenny haniver, well calculated to excite wonder in anyone interested in marine curios.

What is presented as the face of the jenny haniver  is actually the underside of the guitar fish. The ray's real eyes (located on its upperside) are sometimes obscured by curled pectoral fins. Ollie says:

Some people think it's dark, but it's a part of cultural history, of natural history.

Another jenny haniver specimen, which featured in the Museum's 2010 exhibition, The Deep.

In my ongoing quest to uncover the most fascinating and curious specimens and stories from behind the scenes at the Museum, I recently came across this lovely tale that I think epitomises the inquisitiveness, perseverance and patience that it takes to be a good scientist. Let me recount it for you:

In 1973 Dr Peter Whitehead, head of marine fishes at the Museum, began a personal quest that would soon take on international (and interdisciplinary) significance.

Whitehead, an expert in clupeids - herrings, anchovies and their numerous relatives - was attempting to track down the original painting of a fish called a piquitinga. The painting was used as the basis for a woodcut that accompanied a description of the species by the naturalist Georg Marcgraf in Historia naturalis Brasiliae in 1648. Marcgraf's brief Latin description and poor quality woodcut was then used by Carl Linnaeus and later taxonomists, who variously identified it as a herring or as an anchovy.

The woodcut of piquitinga from Marcgraf's Historia naturalis Brasiliae (1648). Detail was lost from the original painting when the book illustrations were made.

Whitehead was determined to get to the bottom of the classification once and for all. He knew that Marcgraf's original paintings were part of a collection known as Theatri rerum naturalium Brasiliae given to Friedrich Wilhelm, Elector of Brandenburg, in 1652. The Elector's library formed the basis of the subsequent Royal Library, which later became the Prussian State Library in Berlin.

During the Second World War, allied bombing made Berlin unsafe, so hundreds of boxes of material were removed from the library and allegedly sent to a Benedictine monastery in Silesia called Grüssau. And that's where the trail went cold.

The materials were not returned to Berlin after the war, and the monastery (now known as Krzeszów) nor the major libraries in Poland knew anything of their whereabouts.

Whitehead admitted that 'the search took on something of an obsession'. Indeed, there are two bulging folders in the Museum's archives - known as the Grüssau file - filled with reams of correspondence relating to the matter.

During his years of detective work Whitehead discovered that as well as the natural history artworks he was looking for, the Prussian State Library had also held many important musical manuscripts by artists including Beethoven, Mozart, Bach and Mendelssohn. These too were evacuated during the war and had not been seen since. He said:

For a year or more I was quite unaware that I had joined one of the biggest and hitherto more frustrating searches for treasures lost during the last war.

Whitehead called on the Polish Ministry of Culture to help, and despite an 'immediate search of all Polish libraries', nothing was found. Undeterred, he 'redoubled his efforts' and began contacting Polish libraries himself.

The breakthrough came in March 1977 with a 'matter-of-fact' letter from Jan Pirozynski at the Jagiellon Library in Krakow: 'I am very glad to be able to tell you that the problem of the lost manuscripts has been cleared up. I have been authorised to tell you that the manuscripts exist... I hope this will be satisfactory to you for this moment'. Understandably, Whitehead was 'absolutely delighted' to hear of the 'miracle'.

It was not until September 1979 that I was able to visit the Jagiellon Library. A trolley was wheeled in bearing seven large volumes. Lifting one of the Theatri, the librarian opened it at a marked page: "There!" he said with a flourish, "There is your piquitinga!" It was a magnificent oil painting and immediately resolved all doubts - it was the small herring Lile piquitinga.

The oil painting of piquitinga from Theatri rerum naturalium Brasiliae, vol 1, p161. Remarkable for its realism, it immediately proved that Marcgraf's fish was the herring Lile piquitinga.

Also contained among the many boxes Whitehead was responsible for tracking down were original scores, in whole or in part, of Beethoven's 7th, 8th and 9th symphonies and his 3rd piano concerto; Mendelssohn's violin concerto and incidental music for A Midsummer Night's Dream; various Bach cantatas; and Mozart's Cosi fan tutte, Marriage of Figaro, and more than 90 other pieces which represented nearly a quarter of all his works known to survive in manuscript.

So that is where Brazilian fish and brilliant composers meet - in boxes in a Polish library, undiscovered for more than a generation.

That Marriage of Figaro, Cosi fan tutte, Beethoven's 9th and piquitinga should reappear after almost 40 years in wooden crates was unbelievable.