A life devoted to painting and pioneering experimentation
In his youth, Karl Tanner took a long time to decide what career to pursue, for there were two hearts beating in his breast – the first for painting, which he had already enjoyed as a child, encouraged by his uncle, the painter Paul Tanner, and by his art teacher. Shortly before leaving school, he was even advised by the latter to become a professional artist. But his other heart beat for the natural sciences – at gymnasium, he had excelled in mathematics. So what was he to do? In the end, he followed the advice of his father, who preferred the idea of his son pursuing a “respectable profession” as a scientist.
Shared enthusiasm for painting
In 1929, after listening in on a number of lectures, Karl Tanner decided to study Chemistry at ETH Zurich. He sensed that, among the various sciences, this would offer the greatest freedom to exercise his fertile imagination. Having earned his diploma, he took a doctorate in the Department of Chemical Engineering. But he was not a model student: repeatedly distracted by painting, he sometimes had to be admonished by his father to return to his books. The distractions were all the greater when he joined the “Carolingia Turicensis” society and met a number of fellow students who shared his passion for painting; he also developed a close friendship with Konrad Escher, who taught History of Art at Zurich University.
Karl Tanner’s second passion – a love of laboratory experimentation – was only fully realized when, in 1938, he took up his first position as a chemist at the Swiss Cable and Rubber Works in Altdorf (Canton Uri). Here, he played a key role in the invention of new synthetic resin applications and insulations. Among the products he developed was a PVC-based artificial leather. Specializing in plastics, he had now discovered the field of research to which he would dedicate the rest of his professional life.
For over 20 years, Karl Tanner served as Plastics Editor for the Swiss industrial journal Technische Rundschau. Later, on account of his specialized knowledge, he was also frequently engaged as an expert witness and consultant. In 1944, given the limited prospects for career development at the Cable and Rubber Works, he joined the Schlieren Dye Works. Here too, however, his freedom to carry out research was increasingly restricted by economic constraints. Finally, in 1956, he was appointed Professor of Chemical Engineering at the Technikum Winterthur, where – alongside his teaching activities – he once again enjoyed sufficient freedom to pursue his research interests and his love of experimentation.
Karl Tanner’s daughter Christine remembers how her father would occasionally return home from the “Tech” with a sooty black face, if something had “gone bang” in the lab again. Fortunately, he was never injured as a result. But his experimentation was not confined to the workplace: in the basement of the family home at Rüschlikon (Canton Zurich), Tanner set up a private laboratory. Here, he investigated, for example, why half a dozen bee stings on the arm appeared to alleviate his rheumatism. Could an antiarthritic agent possibly be developed from bee venom? Or he would happily analyse his wife’s anti-aging cream, concluding that she might just as well apply vegetable oil – chemically they were virtually identical. Over the years, pioneering inventions also emerged, such as an early forerunner of the soft plastic contact lens, or – in collaboration with the dental technician Horst Lustenberger – a modern dental implant. Tanner never patented either of these inventions, even though his neighbour in Rüschlikon was a patent attorney. He hated the idea of getting caught up in red tape and was determined to carry on with his research, always going off in new directions.
Enthusiastic, humorous and helpful
As Christine recalls, her father was interested in almost everything. When she was still a child, during family holidays in Italy, he would take her with him to explore the natural world, or up onto the roof, and his enthusiasm was contagious. Karl Tanner occasionally came home from work with a sooty black face, if something had “gone bang” in the lab again. As well as being adventurous, he was a helpful man, always there when family or friends needed him. In addition, his sense of humour made him good company. Christine also remembers various pranks, such as the occasion when, during his military service, her father in officer’s uniform paid a visit to her mother on horseback – on the first floor of the family home.
Despite his wide-ranging enthusiasms, there was one thing Tanner could not stand – Swiss winters. For this reason, he soon made sure that – at least in his retirement – he would be able to escape to warmer climes. After exploring various options in France and the Valtellina, the family finally found what they were looking for – an almost 200-year-old farmhouse, with no electricity or running water, in Castellina in Chianti (Tuscany). Christine, who was then just completing her architectural studies at evening college, inspected the ruin and spent the winter in Zurich drawing up renovation plans. The building became a family project. Once the restoration work was complete, this became Karl Tanner’s favourite refuge after his retirement in 1974, whenever it got too cold in Switzerland and he wished to paint in tranquillity.
In fact, after he retired, painting again became an increasingly important part of Tanner’s life. But it was only in 1987 that Christine managed to persuade him to exhibit his work in public for the first time. The first painting to be sold was Die Schöpfung (Creation) – a canvas consisting of artificial leather which he had developed himself and painted with home-made paints. Pioneering efforts in chemistry were thus combined with artistic creativity. Karl Tanner had found a way of uniting his two hearts in artistic endeavour. There followed a whole series of successful exhibitions, right up until his death in Rüschlikon in 1998.
During his lifetime, Karl Tanner had been eager to ensure that his estate would benefit the engineering sciences. However, the documents he drafted with a notary were never completed. Accordingly, after his death, his daughter Christine put his wishes into effect via a legacy transferring the houses in Rüschlikon and Castellina in Chianti to the ETH Zurich Foundation. As Christine says, “For offspring, it’s upsetting not to know exactly what purpose one’s parents wished their estate to be used for.” So she is glad her father pointed the way while he was still alive: “The legacy has taken a weight off my mind. It’s reassuring to know that my father’s estate will be in good hands when I’m no longer here.”