After being awarded his Matura in 1869, Gysel studied mathematics at the Polytechnic until 1872. Moreover, he attended lectures on history and art history by Johannes Scherr and Gottfried Kinkel, respectively. Among his mathematics teachers was Geiser, in fact, 'his favourite teacher was the influential Konrad [sic!] Friedrich Geiser' . The two men formed a life-long friendship. Geiser also suggested the topic for Gysel's doctoral thesis Synthetische Untersuchung eines Orthogonalflächensystems , which he submitted at the University of Zurich in 1874 and dedicated to Geiser . Subsequently, Gysel attended mathematics lectures at the University of Bern for a year, notably those by Georg Sidler and Ludwig Schläfli. He remained good friends with the latter until Schläfli's death. A number of letters that both Schläfli and Geiser wrote to Gysel over the course of their decades-long friendships have survived; analyses of these letters and translations can be found in .
Whilst writing his thesis, Gysel worked as a supply teacher for mathematics at the Kantonsschule in Schaffhausen from 1872-1874. He must have made a very good impression, as he was offered a full position upon his return from Bern the following year despite his young age. As was common at the time, the school had two tracks, a classical one and science one. Gysel taught mathematics in the classical track until his retirement in 1926. In addition, he took on responsibility for the physics classes in both tracks until 1919.
According to Schnyder  and Scherrer , Gysel's pupils were always well prepared for university studies, notably at the Polytechnic. Indeed, former pupils attest to the quality of Gysel's teaching in :
Gysel taught as if at university. In physics, we were presented with experimental lectures, broken up by a few revision classes. At this level of education, this is a risk. The success [of this method], with exceptions, was due to the physics experiments, which fascinated the pupils, on the one hand; and to the well-structured, educational lectures on the other hand, paired with excellent experimental skills.However, as Scherrer notes, "according to [Gysel's] own confession, neither particular aptitude, nor specific training or manual skill seemed to predestine him for teaching physics" . Gysel preferred mathematics, and he was well aware of the challenges that faced any teacher of mathematics :
According to Gysel himself, mathematics is the least popular and least enjoyable subject for many pupils, because it demands strict, implacable logic and a selfless devotion to the subject matter. However, he was capable of teaching with such clarity that less talented pupils also profited [from his lessons]; this was because [their] teacher was never scathing about their shortcoming, but tried to support them as much as possible, with great wisdom and patience.Despite all the educational reforms since Gysel's death, his observation about the popularity of the school subject mathematics still holds true today -- surely many of today's mathematics teachers would agree with him.
Gysel greatly influenced the school not only as a teacher, but also in his capacity as headmaster in particular. In 1881 he was appointed deputy headmaster, "which could be seen as an exceptional mark of confidence" . Not only had his predecessor been held in high regard, but also, more importantly, "the powers of the deputy headmaster were vested in a representative of the sciences" . Three years later, Gysel was appointed headmaster, which was the first time that a science teacher was appointed to such a senior position . He only stepped down in 1909. His appointment as headmaster coincided with a general change in education across Switzerland and Germany: during the second half of the 19th century, and particularly towards its end, the sciences became more and more important in the curricula of secondary schools; polytechnics were not only founded, but were also awarded university status . Gysel's passion for physics experiments and technological progress (see paragraph below) is representative of his time. Similarly, his appointment can be seen as an indication of the gradual revaluation of scientists.
During his time in office the school prospered: teaching of the sciences was enhanced, the laboratories were expanded, a third track for future teachers was established in 1897 , the number of pupils doubled, and, as his crowning achievement, the school moved into a new building in 1902.
Gysel aka "Tschuli" was quite popular among his pupils, not only as a teacher, but also as headmaster. As K Bächtold writes in , "it has been attested a hundredfold that the headmaster was an enthusiastic and inspiring teacher, respected and loved by the pupils". The school's pupil corporation, Scaphusia (one of the oldest of its kind in Switzerland and similar to the better known student corporations, whose nearest equivalent in the English-speaking world are the US-American fraternities), awarded him honorary membership in recognition of his benevolence towards the society. For more details see , where an entire chapter is dedicated to Gysel. Furthermore, the dialect writer Albert Bächtold (1891-1981, also from Wilchingen) honoured Gysel's influence on his own life in his novel De Studänt Räbme (1947): The headmaster in the novel, called "Vatter" ("father"), is based on Gysel. The writer described his teacher as follows :
Tschuli: something powerful, clear and straight; you know at first sight that there are no backdoors here, nor any intrigues. [and] You will find such a man only once in a hundred years.Throughout his life, Gysel educated himself further, both in his subjects and in educational matters. He advocated extended and better teaching of physics, and set up the school s physics laboratories. Indeed, "he witnessed and participated in the astounding development of technology"  during his professional life. An example of this interest is the X-ray chamber that he set up in the new school building, and which was used by the local hospital as well. He continued working in the chamber even after his retirement. The new school was also equipped with eight laboratories and two libraries as well as current transformers and a dynamo, which generated the energy needed for physics experiments .
Gysel was also a keen member of the Naturforschende Gesellschaft Schaffhausen, his local Society for Natural Scientists, from 1876 onwards. From 1905-1920 he served as the Society's vice president, and was made an honorary member in 1922. Over the course of the years, he gave a number of talks at the society's meetings as well as elsewhere, predominantly on topics in physics. In addition, he taught experimental physics courses for teachers, and a popular lecture course on radiology in 1920/21 . Gysel became a member of the Deutsche Mathematiker-Vereinigung in 1897. He was also among a large number of Swiss secondary schoolteachers who attended the First International Congress of Mathematicians in Zurich.
His teaching and administrative duties left him little time for research. The list of his publications comprises only seven items: apart from his doctoral thesis, Gysel published three papers on problems in geometry as part of his school's Osterprogramme: Beiträge zur analytischen Geometrie der Kurven und Flächen 2. Grades (1877); Über die sich rechtwinklig schneidenden Normalen einer Fläche 2. Grades (1885); Zur Konstruktion des Schwerpunktes einer ebenen Vielecksfläche (1894). As Uehlinger recounts in , the 1894 paper was, according to Gysel, the most widely recognised one, and included in L Henneberg's Die graphische Statik der starren Systeme (1911). The other publications are a report on the Kantonsschule's new building (1903), an obituary of his friend Jakob Amsler-Laffon (1912), and the chapter on Mathematics, Astronomy, Technology and Physics in the centennial publication of the Naturforschende Gesellschaft Schaffhausen (1923).
On top of his school duties, Gysel took on a number of positions in various committees, which again reflect his interest in education and in technological progress. From 1889-1920 he served on the Erziehungsrat; he also acted as examiner at Matura examinations and the Polytechnic's entry exams for many years. Moreover, he was member of the town's library committee from 1888-1929, responsible for mathematics, astronomy, physics, technology and alpinism. For a while, he was on a committee studying the implementation of electric lighting, and for some years he was a member of the supervisory board of the Light-and-Waterworks Schaffhausen.
In recognition of his contributions, he was made an "Ehrenbürger"-- an honorary citizen, of Schaffhausen in 1922 -- this is comparable to being awarded the Freedom of the City in Great Britain.
On 3 August 1876, Gysel married Barbara Carolina Bollinger from Schaffhausen. In various obituaries their 59-year long marriage is described as a happy one. The couple had two sons and two daughters, as well as nine grandchildren. One of their sons, also called Julius (1881-1972), graduated as a mechanical engineer from the ETH in 1906 and worked for an electric power company. In his obituary, his parents' home is described as a place with 'simple living, hard work, and a lot of music' .
Throughout his life, Gysel was in excellent health -- as Schnyder writes, "during the 53½ years of teaching, [he] was never off sick, even for a single period" . A keen mountaineer, he climbed 33 mountains over 3000 m, and kept up his hobby until his late 70s. He co-founded his local branch of the Swiss Alpine Club and led numerous youth hikes .
Article by: Stefanie Eminger, University of St Andrews