Who Pays When Glass Animals Break?
In 1883, the British Museum complained about six damaged glass animals. Leopold Blaschka blamed the unpacking. His Dresden workshop had made marine life legible for a classroom; getting it there intact was another matter.
What's the deal?
A jellyfish in a museum jar may lose the shape and colour it had alive. In nineteenth-century Dresden, Leopold and Rudolf Blaschka recreated marine animals in glass, preserving the appearance of transparent bodies and delicate tentacles. Museums and universities could show students forms that real preserved specimens no longer displayed clearly, without having to keep the animals alive.
A museum could own a jellyfish and have very little of its living appearance left to show.
Preservation kept the animal available for study, but its shape and colour could change. An anemone that had opened a crown of tentacles in seawater might arrive before the visitor as a contracted body in a jar.
For a zoologist, the specimen remained valuable. It was the animal itself, with structures that could be examined and compared. For someone trying to understand what that animal looked like alive, something was missing.
Leopold and Rudolf Blaschka supplied the missing appearance. From their workshop in Dresden, the father and son made glass anemones, jellyfish, squid, sea slugs and organisms enlarged far beyond their natural size. Museums and universities ordered them through catalogues. Their tentacles stayed extended; their transparent bodies could reveal the arrangement within. A teacher did not have to wait for an animal to open, survive a journey or appear in the right season.
Glass carried its own difficulties. It had to be heated, pulled, coloured, supported and joined. It also had to travel. The letters behind these poised creatures include requests for scientific advice, reminders about unpaid bills and an emphatic disagreement over who was responsible when a box of squid arrived broken.
A glassmaker and his son
Leopold was born in 1822 in northern Bohemia, now part of the Czech Republic, into a family accustomed to working glass, metals and gemstones. He trained in goldsmithing and glassworking. Jewellery and glass eyes belonged to the practical business from which his natural-history models developed.
His interest in sea life reached back to an Atlantic crossing in 1853. In a later account, he recalled luminous forms in the water during a calm. The episode has become a convenient beginning for the glass animals, but roughly ten years separated that voyage from their commercial production. Between the two came other work, new customers and glass plants.
Leopold made naturalistic flowers before marine animals became his special business. The naturalist Ludwig Reichenbach exhibited his plants in Dresden in 1863 and helped bring the animal models to notice. A detailed reconstruction published by Tübingen’s Stadtmuseum traces the first anemones to a request from an unidentified English customer who wanted artificial animals for aquaria. Reichenbach exhibited the results and commissioned further work. The glass animals found buyers among aquarium enthusiasts as well as museum curators.
The family moved to Dresden that year, when Rudolf was six. The city offered schooling for the boy who would eventually share the work. He began learning his father’s craft in his early teens and was working in the business full-time by 1876. The later models are generally attributed to both men. Their collaboration combined the inherited skills of a glass workshop with an increasingly demanding study of zoology.
The sea arrived on paper
Many animals reached the workshop first as illustrations. Philip Henry Gosse’s Actinologia Britannica, published in 1860, was an important source for the early anemones. Later reference material included the work of Ernst Haeckel and other zoologists. The Blaschkas made working drawings from scientific publications, then faced the problem a flat plate could leave unresolved: what happened around the other side?
Gosse’s anemones supplied much more than an outline. His coloured plates showed animals extended, their tentacles separated and their bodies standing above their attachments. They offered a way to recognise an animal that could assume a very different shape when disturbed.
An expanded anemone was a useful choice for teaching, but it was a choice. A model fixed one state of a living, changeable body. Scale could be changed too. A tiny organism could become large enough for a class to inspect; a sequence of models could separate stages of development that were difficult to follow under a microscope.
Books remained essential even as observation from life increased. Rudolf studied marine animals on journeys, and the workshop kept seawater aquaria. Correspondents supplied specimens as well as publications. The network behind an apparently self-contained glass creature could stretch from a marine station to a zoologist’s illustration and then to Dresden.
Observation could include an encounter between animals. One model in the Welsh collection represents an anemone directing stinging threads towards a neighbour. According to the museum, the behaviour had been observed in the Blaschkas’ own aquaria. Here the teaching subject was an interaction, with two bodies arranged to explain what one was doing to the other.
Building a transparent body
The Blaschkas worked glass locally in a flame, a technique called lampworking or flameworking. Instead of gathering a large mass from a furnace, a worker could soften a small section of rod or tube, turn it, stretch it or shape it with tools. Air supplied to the flame helped produce the heat needed for the work.
A fine projection could be drawn from softened glass.
A hollow part could be blown. Separate elements could be fused together, but heat that joined one component could also deform another. Adhesives allowed completed pieces to be assembled without putting the whole animal back through the flame. Wire could support a delicate structure or help hold parts in place.
The finished models were therefore often composite objects. Investigation of the Irish collection has identified materials including wax, paper, gelatine, plaster, wood and animal glue, alongside glass and wire. Similar-looking examples of the same species can have different constructions. The workshop changed its methods as it found better ways to solve a particular problem.
Colour was another decision, rather than a single recipe. The surviving animals include coloured glass and clear glass with applied pigments. Transparent glass could establish a body’s volume while colour picked out structures inside it. A tentacle needed both the right position and enough strength to remain there.
The compromises become particularly clear in correspondence about a sponge’s development. Working from the zoologist Franz Eilhard Schulze’s research, the Blaschkas made a series representing stages of the animal then called Sycandra raphanus. They asked Schulze for corrections and described problems of their own: cells that ought to be more clearly separated, structures that should be visible inside, and a supporting wire that interfered with the representation.
In December 1885 they promised to revise the models according to his advice. They also requested drawings or microscope preparations for difficult forms. By the following February, experiments with the changes had gone well. In the same letter came a request for help securing payment of an earlier bill for 244 marks.
Large enough to understand
A model did not always try to occupy the space of the original animal. The RadiolarianA microscopic, single-celled sea organism, often with a delicate mineral skeleton.Merriam-Webster · radiolarian Aulosphaera elegantissima in Tübingen was enlarged about a hundred times. Its glass lattice made a microscopic form accessible to the unaided eye.
The enlargement served a different purpose from the extended anemone. One selected a useful posture; the other changed size so that relationships could be examined. The sponge series went further, dividing a process into successive objects. What the customer bought might be a likeness, an anatomical explanation or a lesson in development.
Handle with care
By 1878, Henry Augustus Ward’s Natural Science Establishment in Rochester, New York, offered 630 models in its catalogue. A professor could choose animals by number. Harvard’s collection history gives prices ranging from thirty cents to six dollars and fifty cents. Behind the growing catalogue stood a workshop making the objects by hand and arranging for their delivery.
The British Museum’s 1883 order exposes the practical difficulty. Nineteen cephalopod models were listed for dispatch in a case measuring 26 by 22 by 15 inches. The accounts distinguished the models from the case, cardboard boxes and packing. After the shipment arrived, six models became the subject of a complaint about breakage.
In his December reply to the British agent Robert Damon, Leopold argued that the external box had arrived unharmed and suggested that damage had happened during unpacking. He thought broken arm tips could be repaired. Glass, he insisted, travelled on the receiver’s risk. The letter closed with seasonal compliments.
The same correspondence carried better news from much farther away: a collection sent to Canterbury Museum in Christchurch, New Zealand, had arrived safely. Distance alone did not determine whether an animal kept its arms.
At Canterbury the models were eventually displayed among the corresponding zoological material. By 1885, preserved echinoderms and cuttlefish stood alongside glass models. The museum could use both: the actual body and a reconstruction that made aspects of its appearance easier to understand.
Bringing the glass animals back into view
Natural History Museum staff examine the Blaschka models and explain how these fragile animals were prepared for display.
Natural History Museum, LondonWatch on YouTube ↗The workshop turns to flowers
Another teaching problem eventually took precedence. Harvard botanist George Lincoln Goodale wanted lifelike plants for instruction. He visited the Blaschkas in 1886, and botanical work began alongside the animals. Elizabeth Ware and her daughter Mary Lee Ware financed the collection.
In 1890 an exclusive agreement committed the workshop to Harvard. Extensions kept the Blaschkas making plants for the remainder of their careers; commercial animal production did not resume. Leopold died in 1895. Rudolf continued, and the last shipment of botanical models reached Harvard in 1936.
The animals already in museums had a longer and less orderly working life. At Harvard they were distributed among departments according to the groups they represented. Around 1900 many were removed from their original cardboard trays and wired to white plaster plates. The way a model is mounted today can belong to its museum history as well as its making.
Keeping the glass animals together
The models’ survival has made their construction easier to investigate. At Corning, ultraviolet examination of one hydroid model distinguished parts fused with heat from others attached with adhesive. Similar projections had been made from different glasses and joined in different ways. Under ordinary light, much of that work was concealed by the finished animal.
Such discoveries leave less room for a single secret technique, but plenty for the makers’ judgement. An inventory of glass, wire and glue does not specify how much heat to apply or when to stop pulling. Even the objects themselves preserve only part of the working knowledge.
In Wales, earlier repairs had sometimes put tentacles back in the wrong place.
Cleaning presented another difficulty: water could remove dirt, but it could also dissolve original surface paint. Conservators tested alternatives and used white spirit where it removed the dirt without damaging the colour. For reassembly they chose a reversible adhesive, Paraloid B-72, whose comparatively weak bond could fail before the glass broke again.
At Harvard, much of the minor damage has come from the failure of nineteenth-century glue. Conservators restore the contact points with reversible adhesive. The bell or body may have survived intact while the joint that holds a tentacle has given way. To return the animal to its teaching posture, someone must find where the loose part belongs and join it again.
Further reading
- Museum of Comparative Zoology: Blaschka Glass Invertebrates
- Kunstformen des Meeres: zoological models, workshop history and correspondence, Stadtmuseum Tübingen, 2006
- C. Giles Miller and Miranda Lowe: The Natural History Museum Blaschka Collections, 2008
- Matthew D. Shaw and colleagues: Ideas Made Glass, Canterbury Museum, 2017
- National Museum of Ireland: Blaschka Glass Models
- Corning Museum of Glass: Shedding Light on a Blaschka Model
- Museum Wales: Repairing the Irreplaceable
- Corning Museum of Glass: Flameworking
- Harvard Museum of Natural History: The Glass Flowers
- Corning Museum of Glass: Fragile Legacy, models, drawings and workshop materials
- Philip Henry Gosse: Actinologia Britannica, digitised plates