
Foundation and Early Production (1865–1877)
The company R. Fuess was founded in Berlin in 1865 by the precision mechanic Rudolf Fuess. Rudolf Fuess was born on 28 April 1838 in Moringen (Hanover). He learned his trade in workshops in Göttingen and Hamburg and pursued a career as a mechanical instrument maker. After completing his traditional journeyman’s travels—which included employment at the firm Löhm, a manufacturer of leveling instruments—Fuess established his own business in Berlin on 1 April 1865.
The first workshops were located at Mauerstraße 84 in Berlin-Mitte. From April 1865 onward, the firm produced its first mechanical and physical instruments, including pharmaceutical balances and devices for measuring blood pressure, with orders received even from Russia. In parallel, the young entrepreneur also manufactured small consumer goods, such as mechanical gaming dice and knife sharpeners. During this initial phase, the company encountered administrative difficulties, as Fuess—being a native of Hanover—was required to obtain Prussian citizenship in order to operate a business in Berlin. With the support of local authorities, however, he succeeded in securing the necessary permission to establish himself independently.
A decisive breakthrough for the young firm came with a commission from the Berlin Observatory. Fuess succeeded in manufacturing a glass graduated circle only 6 mm in diameter for a telescope eyepiece—a task that other Berlin instrument makers had declined. By accomplishing this highly delicate piece of work, Fuess gained the confidence of the astronomer Wilhelm Foerster, director of the Berlin Observatory, and received further commissions. The company began producing precision astronomical chronographs for the observatory and undertook the preparation of geological specimens, including thin sections for the Geological Institute.
As demand increased, the workshops were relocated several times: in 1870 to Wassertorstraße 46 in the Kreuzberg district; in 1873 to Alte Jakobstraße 108 (the site of today’s Federal Printing Office); and finally, in 1891, in a decisive step, to a newly acquired site at Düntherstraße 8 in Berlin-Steglitz, where a combined residential building and factory was constructed, designed to accommodate approximately 100 workers.
Around 1873–1875, R. Fuess began manufacturing anemometers (instruments for measuring wind speed), which were in demand particularly in the mining industry. Until then, such instruments had largely been imported from England. In 1875, at the request of the geologist Harry Rosenbusch, the Fuess workshop produced the first petrographic microscope manufactured in Germany for the study of minerals. This brass-and-glass instrument, later known as the Rosenbusch microscope, became the prototype for an entire series of polarizing microscopes used in geology and materials science.
In 1877, Rudolf Fuess acquired the financially troubled firm Greiner Jr. & Geißler, which possessed its own glassblowing facilities and specialized in thermometers, barometers, and anemometers. This acquisition significantly expanded the company’s capabilities. In addition to optical and laboratory instruments, R. Fuess now undertook the large-scale production of meteorological equipment, particularly for maritime applications and for the newly established Hamburg Maritime Observatory (Deutsche Seewarte), founded in 1875. During this same period, Fuess patented an original design for the mounting of scales on standard thermometers, a construction that achieved wide dissemination. Through this invention, the firm established valuable scientific connections and initiated collaborations with leading specialists of the era.
Collaboration with Scientists and Company Growth (1877–1914)
After 1877, R. Fuess rapidly developed into one of Germany’s leading manufacturers of precision instruments for science and technology. Fuess personally collaborated with eminent meteorologists, translating their theoretical concepts into practical instruments. Together with the Swiss physicist and meteorologist Heinrich Wild, the company developed a special form of cistern siphon barometer, which was subsequently introduced at all meteorological stations of the Russian Empire. Following the ideas of the meteorologist Adolf Sprung, the firm designed a weight-driven barograph—known as the Sprung–Fuess barograph—for recording atmospheric pressure at the Hamburg maritime station. In collaboration with Dr. Richard Assmann, Fuess constructed the famous aspiration psychrometer (Assmann aspiration thermometer), an instrument for precise humidity measurement that soon became standard equipment in meteorological observatories worldwide.
During the 1880s, the company also produced other recording instruments, including water-level gauges, precipitation recorders designed by Gustav Hellmann (rain gauges with clockwork mechanisms), and devices for registering snow cover. Through this close cooperation between science and manufacture, the Fuess firm attained a leading position in the field of precision meteorological instruments in Germany. Many of its designs achieved the status of standardized “normal instruments” and were used nationwide for calibration and metrological reference.
Beyond meteorology, R. Fuess continued to operate in other domains. In 1886, at the request of the bacteriologist Robert Koch, Fuess constructed a projection apparatus for the demonstration of microscopic specimens—initially using sunlight and later an electric arc lamp. In this way, the company also contributed to the development of medical and biological visualization technologies. By the end of the nineteenth century, the firm’s product range encompassed three major fields: meteorology, hydrotechnics (instruments for measuring water-related parameters), and mineralogy (geological and optical instruments).
Production expanded steadily, and in 1891 the factory moved into its newly constructed premises at Düntherstraße 8 in Berlin-Steglitz, where highly precise mechanical work was carried out by a workforce of approximately 100 employees. With this relocation, the company adopted the trademark “R. Fuess, Berlin-Steglitz”, emphasizing its new location.
By the early twentieth century, R. Fuess had achieved international recognition. Its instruments were supplied not only to scientific institutions in Germany but also abroad. Extensive product catalogues—such as those published in 1887 and 1891—document the broad range of meteorological and laboratory instruments offered by the firm. In addition to scientific customers, industry became an important market: Fuess anemometers were used in mine ventilation systems, thermometers in chemical plants, and hygrometers in tobacco factories. Rudolf Fuess’s reputation was such that his name appeared frequently in specialist literature, and he became a co-founder and editor of the professional journal “Zeitschrift für Instrumentenkunde”.
In 1900, responding to increasing military demand, the company entered a new field by producing optical instruments for the armed forces, including rangefinders and artillery sights. By the outbreak of the First World War, R. Fuess had thus accumulated unique expertise in the manufacture of both scientific and military instruments.
The First World War and the Interwar Period (1914–1933)
In 1913, management of the company passed from the founder to his son, Paul Fuess. Rudolf Fuess died on 21 November 1917. With the outbreak of the First World War, R. Fuess became fully engaged in military production. Orders from the Ministry of War ensured full utilization of the factory, which manufactured high-precision optical sights for small arms and artillery, as well as onboard instruments for aircraft serving the rapidly expanding German air forces.
While the war years brought financial prosperity, the period after 1918 proved extremely difficult. Military orders ceased, and the postwar economic collapse and hyperinflation of 1918–1923 severely hindered the firm’s operations. Like many German enterprises, R. Fuess endured “lean years” during the early 1920s, barely maintaining minimal activity.
By the mid-1920s, conditions gradually improved. Scientific expeditions became an important source of work: the company received orders for instruments used in research journeys, including the famous Arctic and Greenland expeditions led by meteorologist Alfred Wegener. In addition, R. Fuess supplied a complete set of demonstration meteorological instruments for the newly established meteorology hall at the Deutsches Museum in Munich. Export activity also resumed. During this period, the firm opened foreign branches in Yokohama, Bologna, and New York, and established a network of sales agents in dozens of countries. R. Fuess had thus fully become a global enterprise. Nevertheless, the worldwide economic crisis of the late 1920s again dealt a severe blow, and by the early 1930s the volume of orders had declined to a critical minimum.
The Third Reich and the Second World War (1933–1945)
With the rise of National Socialism and the onset of rearmament in Germany, the factories of R. Fuess were once again filled with work. From 1934 onward, drawing on its earlier experience, the company actively developed modern aviation instruments for the Luftwaffe. As part of war preparations, the firm expanded its operations by establishing an additional branch plant in Potsdam, on Düppelstraße, to increase production capacity.
During the Second World War, the company was once again almost entirely devoted to military orders. Production facilities operated at full capacity, and workshops had to be expanded continuously while new workers were recruited. However, the sustained Allied bombing of Berlin made operations increasingly dangerous. Factory facilities were repeatedly evacuated and dispersed to avoid total destruction. Despite these measures, by the end of the war the situation had become catastrophic: both the main plant in Steglitz and the Potsdam branch were destroyed, and remaining equipment was partially removed or dismantled by occupying forces. By the spring of 1945, R. Fuess lay in ruins, having lost both its production facilities and its markets amid the general devastation of postwar Germany.
A memorial source associated with the Flossenbürg concentration camp memorial describes the subcamp Außenlager Schönheide (21 February 1945–13 April 1945) and explicitly states that some prisoners were employed for the evacuated Berlin-Steglitz firm R. Fuess, identified as a manufacturer of aircraft components, operating in a former textile factory building.
Postwar Recovery and Closure (1945–1976)
After 1945, R. Fuess attempted to resume operations under radically changed conditions. In the immediate postwar years, when demand for scientific instruments was minimal, the company temporarily shifted to the production of utilitarian consumer goods. This strategy allowed part of the workforce and production base to be preserved until the early 1950s, when renewed interest in precision instrument making emerged with the reconstruction of science and industry. By 1950, the firm again demonstrated its innovative capacity, becoming the only manufacturer in Germany to develop an ultraviolet spectrograph of its own design and creating the “Böenschreiber 90z”, a recording instrument for measuring gust wind parameters.
Nevertheless, in subsequent decades the industry changed rapidly under the influence of electronics. Electronic measuring instruments increasingly displaced mechanical ones, and the traditional strength of R. Fuess—mechanical precision—lost its competitive advantage. Although the company attempted to adapt, its situation deteriorated steadily from the early 1970s onward. In 1975, R. Fuess officially ceased operations. The factory buildings at Düntherstraße 8, once a symbol of Berlin precision engineering, were demolished in late 1976. Today, a residential building stands on the site, and the name R. Fuess narrowly escaped complete oblivion.
Legacy and Successors after 1976
Despite the liquidation of the company, its legacy continued. In the final years of R. Fuess, one of its principal suppliers was the engineer Alfred Müller, whose small firm provided components for meteorological instruments. Anticipating the closure of the historic factory, Dr. Müller founded Dr. Alfred Müller Meteorologische Instrumente KG in 1975, acquiring part of the equipment and technical documentation of R. Fuess and employing several experienced Fuess workers. The new company, located in Königs Wusterhausen near Berlin, continued the production of analog meteorological instruments based on classical designs. Many products continued to be manufactured according to original R. Fuess models, bearing the historic name on their scales alongside the new Müller brand.
Although Dr. Müller’s company does not present itself as the formal legal successor of R. Fuess, it effectively preserved the spirit and traditions of the Berlin enterprise. As a tribute to this heritage, references to “r.fuess berlin steglitz” appear in the company’s web and email addresses. Today, instruments bearing the R. Fuess name continue to be produced by Dr. A. Müller, and they still find users worldwide. The Fuess name remains synonymous with the highest standards of quality and precision. By manufacturing a wide range of equipment—from meteorological barometers and anemometers to polarizing microscopes and aviation instruments—R. Fuess secured a lasting place in the history of science and technology. Its catalogues and instruments are now prized by collectors, cited in scholarly literature, and sustained by successors who continue this unique tradition of German precision instrument making.