The ERMETH (''Elektronische Rechenmaschine der ETH'', German for Electronic Calculating Machine of the ETH) was one of the first

computers A computer is a machine that can be programmed to automatically carry out sequences of arithmetic or logical operations ('' computation''). Modern digital electronic computers can perform generic sets of operations known as ''programs'', ...

in Europe and was developed and built by

Eduard Stiefel Eduard L. Stiefel (21 April 1909 – 25 November 1978) was a Swiss mathematician. Together with Cornelius Lanczos and Magnus Hestenes, he invented the conjugate gradient method, and gave what is now understood to be a partial construction of th ...

and his team of the Institute for Applied Mathematics at the

ETH Zurich ETH Zurich (; ) is a public university in Zurich, Switzerland. Founded in 1854 with the stated mission to educate engineers and scientists, the university focuses primarily on science, technology, engineering, and mathematics. ETH Zurich ran ...

between 1948 and 1956. It was in use until 1963 and is now displayed at the Museum of Communication Bern (

Switzerland Switzerland, officially the Swiss Confederation, is a landlocked country located in west-central Europe. It is bordered by Italy to the south, France to the west, Germany to the north, and Austria and Liechtenstein to the east. Switzerland ...

Models

Eduard Stiefel and his two senior assistants

Heinz Rutishauser Heinz Rutishauser (30 January 1918 – 10 November 1970) was a Swiss people, Swiss mathematician and a pioneer of modern numerical mathematics and computer science. Life Rutishauser's father died when he was 13 years old and his mother died t ...

and

Ambros Speiser Ambrosius Paul Speiser (November 13 1922, in Basel – May 10 2003, in Aarau) was a Swiss engineer and scientist. He led the development of the first Swiss electronic computer. Speiser studied electrotechnology at Eidgenössische Technische Hoc ...

were inspired by models in the USA and

United Kingdom The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Northwestern Europe, off the coast of European mainland, the continental mainland. It comprises England, Scotlan ...

when developing the ERMETH. In 1949 Rutishauser and Speiser undertook study trips to

Howard Aiken Howard Hathaway Aiken (March 8, 1900 – March 14, 1973) was an American physicist and a list of pioneers in computer science, pioneer in computing. He was the original conceptual designer behind IBM's Harvard Mark I, the United States' first C ...

(

Harvard University Harvard University is a Private university, private Ivy League research university in Cambridge, Massachusetts, United States. Founded in 1636 and named for its first benefactor, the History of the Puritans in North America, Puritan clergyma ...

John von Neumann John von Neumann ( ; ; December 28, 1903 – February 8, 1957) was a Hungarian and American mathematician, physicist, computer scientist and engineer. Von Neumann had perhaps the widest coverage of any mathematician of his time, in ...

(

Princeton University Princeton University is a private university, private Ivy League research university in Princeton, New Jersey, United States. Founded in 1746 in Elizabeth, New Jersey, Elizabeth as the College of New Jersey, Princeton is the List of Colonial ...

) and to the

University of Cambridge The University of Cambridge is a Public university, public collegiate university, collegiate research university in Cambridge, England. Founded in 1209, the University of Cambridge is the List of oldest universities in continuous operation, wo ...

, which operated the

EDSAC The Electronic Delay Storage Automatic Calculator (EDSAC) was an early British computer. Inspired by John von Neumann's seminal ''First Draft of a Report on the EDVAC'', the machine was constructed by Maurice Wilkes and his team at the Universit ...

. In 1950, Stiefel rented for five years the only existing digital computer in continental Europe at that time, the Zuse Z4, completed by

Konrad Zuse Konrad Ernst Otto Zuse (; ; 22 June 1910 – 18 December 1995) was a German civil engineer, List of pioneers in computer science, pioneering computer scientist, inventor and businessman. His greatest achievement was the world's first programm ...

in 1945, for the ETH in order to gain experience with a calculating machine during the construction of the ERMETH.

Technical concept

The ERMETH had (in contrast to the Z4) a classical

von Neumann architecture The von Neumann architecture—also known as the von Neumann model or Princeton architecture—is a computer architecture based on the '' First Draft of a Report on the EDVAC'', written by John von Neumann in 1945, describing designs discus ...

, i.e. it was a calculating machine in which program and processed data were stored in the same main memory; thus, numbers, as well as program parts, could be processed automatically. The ERMETH was designed for numerical calculations and worked in true decimal (not binary or hexadecimal) and had instructions for all four basic arithmetic operations with floating-point and fixed-point numbers, but not for processing letters. At the start of operation (1956), it consisted of devices ( hardware) and stored user programs (

software Software consists of computer programs that instruct the Execution (computing), execution of a computer. Software also includes design documents and specifications. The history of software is closely tied to the development of digital comput ...

), but had no

operating system An operating system (OS) is system software that manages computer hardware and software resources, and provides common daemon (computing), services for computer programs. Time-sharing operating systems scheduler (computing), schedule tasks for ...

, so that each user had to first read in his program, which had already been prepared on punch cards in machine language and then start it by setting the program counter to the first command. Under program control, user data was then read in (from punch cards) and parameter values were requested (via the keyboard) from the user. Already in 1952, Heinz Rutishauser had presented the concept of the

compiler In computing, a compiler is a computer program that Translator (computing), translates computer code written in one programming language (the ''source'' language) into another language (the ''target'' language). The name "compiler" is primaril ...

for the use of machine-independent computer languages in his habilitation thesis on "automatic computation plan production". Thanks to the development of the higher programming language

Algol ALGOL (; short for "Algorithmic Language") is a family of imperative computer programming languages originally developed in 1958. ALGOL heavily influenced many other languages and was the standard method for algorithm description used by the ...

(Algol 58 and Algol 60), machine-independent programming later became possible; for the input of letters, the ERMETH 1958 had to be supplemented with a paper tape reader. The ERMETH had an arithmetic unit with 1,500 electron tubes. A 1.5-ton

magnetic drum Drum memory was a magnetic data storage device invented by Gustav Tauschek in 1932 in Austria. Drums were widely used in the 1950s and into the 1960s as computer memory. Many early computers, called drum computers or drum machines, used dru ...

with space for 10,000 words to 16 decimal places (14 digits, sign, check digit), which rotated at 100 revolutions per second, served as the main memory. This also determined the operating speed of the ERMETH per command step, because the average access time to the commands and numbers stored on the drum was 5 milliseconds; the much higher operating speed of the electron tubes did not change this. The use of the 10'000 words of the working memory was very flexible. For each word (with 16 decimal places), either a floating-point number (11 valid digits, 3-digit exponent, sign and check digit), a fixed point number (14 digits, sign, check digit) or two instructions (2 digits for instruction type, 1 digit for index register, 4 digits for memory address) could be stored. An example: The

developed by

Hans Rudolf Schwarz Hans may refer to: __NOTOC__ People * Hans (name), a masculine given name * Hans Raj Hans, Indian singer and politician ** Navraj Hans, Indian singer, actor, entrepreneur, cricket player and performer, son of Hans Raj Hans ** Yuvraj Hans, Punjabi a ...

for Algol 60 programs occupied 4,000 memory cells with double instructions so that 6,000 cells remained available for an application program and its user data. If this was not enough, all 10,000 cells could be used, but only after overwriting the compiler. In this case, however, the compiler had to be reloaded before the next Algol program from punch cards, which alone took almost an hour. For numerical data input, mainly

punch card A punched card (also punch card or punched-card) is a stiff paper-based medium used to store digital information via the presence or absence of holes in predefined positions. Developed over the 18th to 20th centuries, punched cards were wide ...

s of the type Remington-edge with 90 columns were used, later on also 5-channel

punch tape file:PaperTapes-5and8Hole.jpg, Five- and eight-hole wide punched paper tape file:Harwell-dekatron-witch-10.jpg, Paper tape reader on the Harwell computer with a small piece of five-hole tape connected in a circle – creating a physical program ...

for Algol program input. Data output was either on punched cards or on an

IBM International Business Machines Corporation (using the trademark IBM), nicknamed Big Blue, is an American Multinational corporation, multinational technology company headquartered in Armonk, New York, and present in over 175 countries. It is ...

typewriter A typewriter is a Machine, mechanical or electromechanical machine for typing characters. Typically, a typewriter has an array of Button (control), keys, and each one causes a different single character to be produced on paper by striking an i ...

, which, however, also output only digits. Thus, punched cards could also be used for intermediate storage of large amounts of data as secondary storage. The electrical power consumption of the ERMETH was 30 kW. It reacted sensitively to fluctuations in the mains voltage, for example when the tram went into operation in the morning. In 1955, Heinz Rutishauser became an associate professor at the ETH Zurich and Ambros Speiser left to the industry, becoming the founding director of the

IBM Zurich Research Laboratory IBM Research is the research and development division for IBM, an American multinational information technology company. IBM Research is headquartered at the Thomas J. Watson Research Center in Yorktown Heights, New York, near IBM headquarters i ...

Rüschlikon Rüschlikon is a Municipalities of Switzerland, municipality in the district of Horgen District, Horgen in the Cantons of Switzerland, canton of Zürich (canton), Zürich in Switzerland. It is located on the west shore of Lake Zürich. Coat of ar ...

. From there on, the completion of the ERMETH was supervised by and Alfred Schai. With various technical and financial setbacks, the ERMETH was built up as a one-off unit from 1955 onwards and gradually put into operation from 1956 onwards; it performed its task until October 1963, when it was dismantled and packed. A planned licensed version of ERMETH by a private company did not come about. After spatial alterations a CDC 1604A of

Control Data Corporation Control Data Corporation (CDC) was a mainframe and supercomputer company that in the 1960s was one of the nine major U.S. computer companies, which group included IBM, the Burroughs Corporation, and the Digital Equipment Corporation (DEC), the N ...

took its place from April 1964. The available computing power at ETH increased by a factor of 100 with the transition from the electromechanical Z4 to the ERMETH, but by a factor of 400 with the transition from the ERMETH with its time-critical magnetic drum memory to the fully electronic CDC 1604A.

Deployment

The ERMETH has been used in research and development for very different tasks. The employees of the Institute of Applied Mathematics used it for their own scientific topics to develop numerical algorithms and working aids in the sense of first operating system components. But they were also active as consultants and helpers for computing work of other ERMETH users. They came from the ETH and other universities as well as from industry and from civil and military federal agencies. The ERMETH was also used in teaching. Optional programming lectures were held from the 1950s onwards, and there were also exercises (in groups) on the computer system. If students had written a program and transferred it to punched cards, they could hand in their punched card package and, depending on the program quality, received the expected or a wrong result or even a program abort printed out the next day.

ERMETH today

After its dismantling in 1963, the ERMETH was stored for the time being as an important exhibit for the planned Technorama in

Winterthur Winterthur (; ) is a city in the canton of Zurich in northern Switzerland. With over 120,000 residents, it is the country's List of cities in Switzerland, sixth-largest city by population, as well as its ninth-largest agglomeration with about 14 ...

and then exhibited there from 1982 to 2004. Since the end of 2006, it has been on permanent loan from ETH Zurich to the Museum of Communication in

Bern Bern (), or Berne (), ; ; ; . is the ''de facto'' Capital city, capital of Switzerland, referred to as the "federal city".; ; ; . According to the Swiss constitution, the Swiss Confederation intentionally has no "capital", but Bern has gov ...

External links

''ERMETH - Elektronische Rechenmaschine der ETH.''
* ETH Zürich
Kulturgüterkatalog: ERMETH.
* Zehnder, Carl August
''ERMETH und Lilith im MTW.''

References