De anatomische preparaten van Frederik Ruysch

The history of Ruysch's anatomy

Anatomical lesson by Dr. Frederik Ruysch, 1683 Jan van Neck (1634/35 - 1714) oil on canvas, 141 x 203 cm. Amsterdam Historical Museum SA 2644.

Researchers trying to understand the working of the human body, encountered huge technical problems, because of the rapid decay of corpses. Around 1650 a corpse could only be used for a few days; enough time to educate students, but not enough to find the answer to complicated research questions.

Anatomists had to repeat their dissections for further research and to demonstrate their findings to others. This was a very inefficient method, and a very unpleasant one, working covered in blood in the stench of decay. Then there was the permanent lack of bodies. But the biggest problem was that the researcher had to hurry to outrun the decay. Mistakes and misunderstandings were caused by this haste, both in the dissection as in the representation of the findings.

Drawing in haste

A drawing had to be made during the dissection. This drawing would be worked out, engraved, and published, when the anatomist decided to publish his findings. This was how dissectors informed each other of their discoveries. Because of the speed of their making, pictures were often not very clear. If dissected body parts could be preserved longer, more precise drawings could be made, and on top of that it would be possible to check them. There was an urgent need for a method to fight decay and store body parts.

The discovery of alcohol

In antiquity people had tried to store corpses in a conserving fluid (to replace the tissue fluids). The method had never really proved successful until alcohol was used. Two students of Leiden University, Frederik Ruysch and Jan Swammerdam were among the first to successfully apply alcohol. Both came from a practical background; Swammerdam had been brought up in a pharmacy and Ruysch was a pharmacist himself. They developed methods to conserve tissue in alcohol, while searching for more solutions for the technical problems they encountered in their anatomical research.

Frederik Ruysch, Injecting the pia mater

White wax

The vascular system, transporting blood and liquids throughout the body, constituted the greater part of their research. By filling them with a liquid or with air they could be made visible. At first this was done using small copper pipes, but because this was a time-consuming method another student from Leiden, Reinier de Graaf, had come up with a syringe. The course of the blood-vessels was made clearly visible, but the injected body parts could not be dissected until Swammerdam came up with a solution. Instead of liquids Swammerdam used white wax that he heated and melted before injecting it into the vessels. After the cooling down of the liquid a permanent specimen remained, a specimen that would not run leak during dissection. Ruysch copied this technique and refining it he succeeded in the end to make it possible to see very delicate parts of the human body.

Preparates on show

Swammerdam en Ruysch stored their specimens and were the first to have collections not mainly consisting of bones. The specimen were used as a basis for research, but layman were also keen to see them. The interest was so enormous that Ruysch mounted an exhibition next door from his house on the Nieuwezijds Achterburgwal in Amsterdam and charged for admission. Here visitors could see internal organs that had kept their natural shape, thanks to the wax injections. The specimen had acquired a natural complexion through the reddening of the wax. To many it was a staggering experience and soon the exhibition became an attraction.


In the mid-eighties Ruysch moved to the Bloemgracht, where he furnished a real museum. His visitors represented different categories. Firstly there was the public to whom the museum was mainly a strange entertainment. These visitors had to pay an admission fee. One of Ruysch daughters gave them a guided tour. Physicians had free entrance and if necessary Ruysch himself would give them information. For physicians, with a real interest in anatomy, he lectured, using his collection as instruction material. He had a bilingual catalogue printed. Latin for the learned and the foreigners to use, and Dutch for the other visitors. His collection filled ten large cupboards, 'cabinets' and a few smaller cupboards.

Frederik Ruysch, Penis cut in slices

Unborn children

The different positions that Ruysch held, all resulted in bringing in new material. Some body parts belonged to people sentenced to death, that he had dissected being the surgeons' teacher. Other body parts he had acquired as a surgeon-obstetrician, a court doctor or a teacher of midwives. He had at his disposal aborted unborn foetuses and corpses from the mortuary. He possessed body parts from miscarried foetuses, from babies that had died shortly after the delivery, from women who had died during labour, and people who had died in accidents. He collected embryos in all stages of growth. In his museum visitors could see the development of creatures the size of a grain of sand into fully developed babies. Other dissectors all tried to copy his preparation techniques, but they did not achieve his level of subtlety. No one put so much effort into the presentation.

Reaching for perfection

Near the end of the 17th century Frederik Ruysch perfected his preparation method, with the help of his son, thus making it possible that, so he says: 'Entire persons with all their intestines can be kept without decay for centuries, and maybe, I think, forever'. In preparation it was vital one injected a substance that only solidified after it had reached the smallest vessels. Liquid wax went a long way, but not as far as Ruysch wanted it to go. He had been searching for a substance that could improve the process. On top of that he had experimented with new techniques that carried the injected matter as far into the tissue as possible. For instance he would pour warm water for several hours over a body part that he wanted to inject. The greatest improvement occured a new liquid, that he successfully could inject into the smallest vessels and this technique led him to all sorts of new discoveries.

Preparation of Ruysch fastened to a board by pins to draw the injected vessels.

Looking alive

Through injecting them with his new liquid, Ruysch was able to prepare body parts in such a fashion that their appearance hardly differed from their life appearance. Most of his specimen were kept in glass jars and bottles, in a very clear liquid, his 'liquor balsamicus'. In this liquid they not only kept their lifelike appearance, but they also stayed flexible. This was the main difference with his first method, in which 'the objects became hard and everlasting, but they also changed in colour and appearance'.

Witchcraft and trics

At the first exhibitions of the results of his technique people spoke about it as if it was witchcraft. Visitors in his museum and attendants at his lectures all expressed their amazement and their bewilderment. But there was also a certain amount of disbelief. Some people thought that Ruysch used trickery to improve the appearance of his specimen. And the way he exhibited his anatomical material was criticised. Why all these decorations? 'I do this to take away from these people all repulsion, the natural reaction of people confronted with corpses being one of fright'.

Better than a microscope

Using his new technique, Ruysch wanted to add to the knowledge of the structure of organs. Since the start of anatomical research of human bodies, all parts of the body that were visible with the naked eye had been described and depicted. The microscope had slighty increased the possibilities of the eye. Ruysch thought that his method allowed you to see even more than a microscope did, and in a lot of cases he was right, but the image was often distorted when the specimen was rinsed in water (causing tissue parts to dissolve) and when liquid ran out of the most delicate vessels. And in the end the human body proved to be constructed in a much more delicate and complicated manner than Ruysch could possibly have dreamed.

Luuc Kooijmans, historian, Utrecht, The Netherlands