# Mystery Dating of the World-famous 'Millionaire' Calculating Machine Solved

By Herbert Bruderer

October 15, 2018

Millionaire: A machine full of riddles
In the history of mechanical calculating machines, the "Millionaire" occupies a prominent position due to its type of construction. To this day, the machine has not revealed many of its secrets. The origin of its strange name has still not been clarified. One also does not know until when it was produced. It is also unclear how the serial numbers were used and how they can be assigned to the years of manufacture. The determination of age is therefore associated with great uncertainties. This is also confirmed by an international survey among museums. Engineers are still struggling to understand how the highly complex direct multiplication body works. Only since the discovery of new documents at the Museum für Kommunikation in Berne in September 2018 has it become clear how many copies of the machine have been manufactured.

Neither year of manufacture nor type of machine
If no year of manufacture is engraved on the calculators, and if no accompanying documents are available, dating is often quite hard. This also applies to the then-world-famous Swiss direct multiplier "Millionaire." This heavyweight device, manufactured by H.W. Egli SA in Zurich from 1893, mastered all four basic arithmetic operations. I am trying to determine the construction time using the mysterious serial numbers. As a rule, the surviving Millionaire machines do not bear any information on the model, which makes dating even more difficult. There were 21 different types of Millionaires (including the Excelsior model). In addition to the Millionaire direct multiplying machine (see Fig. 1), Egli manufactured another successful stepped drum machine, the Madas.

Fig. 1: This Millionaire machine has a 4-digit setting mechanism (top middle)
and a 10-digit accumulator (bottom).
The numbers are entered with sliders. With the crank (top right),
the values are transferred to the result register.
Credit: Museum für Kommunikation, Berne

Documents with information on the number of Millionaires manufactured have come to light
New documents, which came to light on 13 September 2018 in the Museum für Kommunikation in Berne, facilitate the allocation of the year of manufacture. For the first time since the dissolution of the company about 50 years ago, exact quantities for all Millionaire and Madas calculating machines produced by Egli are known. A total of 5,074 Millionaire machines (plus an additional 25 Excelsior machines) were manufactured (see Fig. 2). The reason for this investigation was a message that the first machines were sold in 1897 (one to ETH Zurich) and an erroneous dating (by Empa, Dübendorf ZH, and the collection center of the Swiss National Museum, Affoltern ZH) of a machine to 1895.

Fig. 2: Development of the number of copies of the Millionaire calculating machine.
Based on the information provided by H.W. Egli SA, Zurich,
the annual number of units manufactured or sold was calculated approximately.
Credit: Bruderer Informatik, CH-9401 Rorschach, Switzerland 2018

H.W. Egli SA, Zurich: Millionaire and Madas

Mass production

Millionaire      1896–1941

Note

The Millionaire was sold until at least 1941.

Quantity

Millionaire            5,099

Eos (licence)         1,250

Gesamt                94,313

Note:
The 5,099 pieces contain 25 copies of the Excelsior.

Company Dates
Foundation of the company: 1893
Dissolution of the company: 1972

Remarks:
The Madas was manufactured from 1913 to 1968, sales began in 1914, therefore all maker numbers up to this point refer to the Millionaire. It is often said that the Millionaire was produced until 1935. However, this date is not documented. A letter dated 20 November 1967 from H.W. Egli SA to a customer states that the manufacture of the Millionaire calculation machine was discontinued 40 years earlier, i.e. around 1927 (see Gérald Saudan: Swiss calculating machines. H. W. Egli A.-G., page 70). The catalogs of the Swiss Mustermesse (sample fair) show that this machine was exhibited in Basel until 1938 (see Herbert Bruderer: Meilensteine der Rechentechnik, vol. 1, page 581). According to an unpublished compilation by the company, 5,099 units of the millionaire were sold by the end of 1941 (i.e., 66 units since 6 October 1933). The technical literature often mentions the production of 4,655 Millionaire machines. This number is inaccurate.

With the introduction of the sister machine Madas with automatic multiplication (1927) and the portable Madas (1931), the sales of the millionaire probably decreased strongly, especially as the division with the Millionaire was quite cumbersome.

Deviations from earlier investigations
Lewin assumes a common numbering system of the Millionaire and the Madas. According to his diagram of 1992, which covers the period from 1895 to 1931, the serial number 500 corresponds to the year 1900. Up to this date, however, only about 150 machines had been built (see Michael Lewin: Entwicklungsgeschichte der Rechenmaschinen der Firma H.W. Egli bis 1931, part 2, page 11). For 1905 he mentions more than 1,500 pieces, but up to this point only about 400 had been produced. For the year 1913 (introduction of the Madas) he assumed the serial number 3500, but according to Egli's documents there were about 2,200 copies of the Millionaire.

Saudan separates the allocation of serial numbers for the two devices. His diagram (2017) covers the years 1893 to 1924. For 1905 and 1910 he reckons with 500 and 1500 pieces, respectively, which comes quite close to the values of the manufacturing company (about 400 and 1600, respectively) (see Gérald Saudan: Swiss calculating machines. H. W. Egli A.-G., page 73). At the beginning of the sales of the Madas (1914), he estimated the serial number of the Millionaire at around 2400 (according to the author's calculations, there were about 2300). For 1918 he comes to No. 3500 (about 3000). For 1918 and 1921, he draws a jump of 500 (from 3500 to 4000) and 1500 numbers (4500 to 6000), respectively.

For Saudan, the numbers 3500 and 4000 (gap) correspond to 1918, the numbers 4500 and 6000 (gap) to 1921. The number 6500 is assigned to 1924. In these cases there are deviations of 1 to 3 years from my assumptions.

Because of the missing data, I was not able to find out whether there are contradictions to the years of introduction of the different machine types.

Assignment of serial numbers to years of manufacture
The following tables attempt to establish a relationship between the serial numbers and the year of manufacture and to learn more about the connection with the legal form of the maker (see Tab. 1 to 7).

Millionaire calculating machine

 Tab. 1: Dating based on serial numbers (1896-1916) Serial Year of numbers manufacture Annual Production 1–12 1896 12 13–300 1897–1904 288 301–410 1905 110 411–600 1906 190 601–830 1907 230 831–1050 1908 220 1051–1350 1909 300 1351–1634 1910 284 1635–1911 1911 277 1912–2237 1913 326 2238–2369 1915 132 2370–2537 1916 168 Total 2537 Tab. 2: Distribution over the years 1897 to 1904 (estimate) Serial Year of numbers manufacture Total 13–48 1897 49–84 1898 85–120 1899 121–156 1900 157–192 1901 193–228 1902 229–264 1903 265–300 1904 288 Tab. 3: Distribution over the years 1912 to 1915 (estimate) Serial Year of Total numbers manufacture 1912–2074 1912 163 2075–2237 1913 163 2238–2303 1914 66 2304–2369 1915 66 Total 458

Remarks:
The year of construction can be derived roughly from the data on the number of calculators manufactured annually. However, these are only approximate values. For the years 1912 and 1914, as well as 1917 and later, no exact quantities are available. No. 7 should be dated 1898. This is a contradiction to (later-written) documents.

According to the inventory of the Webmuseum of John Wolff, the Millionaire No. 1079 was used for the first Australian census (1911), the date of purchase is open. The Shawmut Mining Co., St. Mary's, Pennsylvania, is said to have acquired No. 1338 in 1909. No. 1829 was located from about 1910 in the observatory in Sydney. A machine used by the New York Central Railroad Co. with the No. 2015 was manufactured in 1912. These four examples confirm that the allocation of the years of construction up to 1912 is reasonably correct.

As a survey from autumn 2018 shows, the "Register of Millionaire calculators" by John Wolff's web museum is incomplete.

Tab. 4: Uncertain classification from 1917 to 1933 (estimate)

 Serial Year of numbers manufacture Total 2538–2777 1917 240 pieces/year 2778–3017 1918 3018–3257 1919 3258–3497 1920 960 4001–4200 1921 200 pieces/year 4201–4400 1922 400 6001–6120 1923 120 pieces/year 6121–6240 1924 6241–6340 1925 100 pieces/year 6341–6440 1926 6441–6540 1927 6541–6640 1928 6641–6740 1929 6741–6840 1930 6841–6940 1931 6941–7040 1932 7041–7111 1933 1111 71 pieces Gesamt 2471 Average/year 145,353

Remarks:
From 1917 to 1933, 2,471 units (5008-2537) were produced, an average of 145.35 units per year. With the advent of electric four-function machines,  annual production fell sharply from about 1930 onwards. This allocation is based on the production of an average of 145 pieces/year.

It is assumed that all mass-manufactured machines (and models) were numbered consecutively from No. 1. Obviously, there were large gaps. Jumps in the numbering (e.g., new counting for certain models) and the common numbering with the Madas (probably from 1924) have the consequence that the manufacture time shifts forward; i.e., the machines are several years older. This should be especially true for the machines from about 1928 onwards. The determination of the year of production thus becomes more and more uncertain (from No. 6500). Gaps in the numbering system and a common numbering promote the marketing, but make the dating more difficult. This can also deceive competitors.

Until October 1933, 5,008 Millionaire machines (+ 25 Excelsior) were manufactured, until the end of 1941 66 copies were added. On average, that is still 8.25 pieces/year.

The following information can be taken from John Wolff's list: The U.S. Department of Agriculture allegedly bought No. 2372 around 1911. No. 2566 was used from 1917 by the Metropolitan Gas Co. in Melbourne. The Millionaire 4307 was acquired by Rothamsted Research in Harpenden, Herts, in 1919 for statistical purposes, the number 6338 was acquired in 1923.

The Musée de la machine à écrire, Lausanne, has a Millionaire with number 6443. It is equipped with a multiplication keyboard introduced in 1927.

The reliability of the Wolff directory can only be checked to a limited extent. Especially the date of purchase from the Ministry of Agriculture seems uncertain. The determination of the years of manufacture based on the serial numbers seems to apply more or less until 1927.

The National Museum of American History, Washington, D.C., has two copies with the numbers 2432 and 2609. In both cases Hans W. Egli is mentioned as the maker, they were obviously built before 1918. This also applies to the No. 2505 of the Heinz-Nixdorf-Museumsforum in Paderborn and the No. 2770 of the Canada Science and Technology Museum, Ottawa.

The machines No. 3044 and 4062 of the Museum für Kommunikation in Berne, the No. 3260 of the Abteilung Amtliche Vermessung of the City of Zurich and the No. 3282 of the Collection of Historical Scientific Instruments of Harvard University bear a plate with the company name H.W. Egli SA. They were probably manufactured in 1918 at the earliest.

Tab. 5: Boundary between sole proprietorship and joint-stock company

 Serial number Maker 2432 Hans W. Egli 2505 Hans W. Egli 2609 Hans W. Egli 2653 Hans W. Egli 2741 H.W. Egli AG 2770 Hans W. Egli 2851 H.W. Egli AG 2918 H.W. Egli AG 3044 H.W. Egli AG 3177 Hans W. Egli 3260 H.W. Egli AG 3282 H.W. Egli AG 4062 H.W. Egli AG 4089 Hans W. Egli

Note:
The Millionaire machines carry a name plate of the company H.W. Egli AG from about no. 2800. However, there are also exceptions (for unknown reasons): Sometimes the manufacturer's details are missing, sometimes the company plates were replaced by the representatives' own plates.

For the Millionaire, about 10,000 serial numbers are missing.

Around 5,100 Millionaire machines were produced, but the serial numbers run up to over 17,000. So there are about 10,000 serial numbers missing. Most numbers were apparently assigned to the Madas. From the foundation of the company (1893) to its liquidation (1972), H.W. Egli AG produced 94,313 calculating machines: 5,099 Millionaire (including Excelsior), 87,964 Madas, and 1,250 Eos.

Tab. 6: Dating based on serial numbers (summarizing estimate: 1896-1933)

 Serial numbers Year of manufacture 49–84 1898 85–120 1899 121–156 1900 157–192 1901 193–228 1902 229–264 1903 265–300 1904 301–410 1905 411–600 1906 601–830 1907 831–1050 1908 1051–1350 1909 1351–1634 1910 1635–1911 1911 1912–2074 1912 2075–2237 1913 2238–2303 1914 2370–2537 1916 2538–2777 1917 2778–3017 1918 3018–3257 1919 3258–3497 1920 4001–4200 1921 4201–4400 1922 6001–6120 1923 6121–6240 1924 6241–6340 1925 6341–6440 1926 6441–6540 1927 6541–6640 1928 6641–6740 1929 6741–6840 1930 6841–6940 1931 6941–7040 1932 7041–7111 1933 © Bruderer Informatik, CH-9401 Rorschach, Switzerland 2018

Remarks:
According to Gérald Saudan, the serial numbers 3501–4000 and 4501–6000 were reserved for the Madas. The numbers from 6501 to 14000 were used for the Madas and occasionally for the Millionaires (see Gérald Saudan: Swiss calculating machines. H. W. Egli A.-G., page 71). From 1928 onwards, the determination of the years of manufacture becomes rather uncertain. The numbers 3498 and 3499 are assigned here to the year 1919, the numbers 4401–4500 to the year 1922. Whether these numbers (from 4401) were actually assigned is open.

Tab. 7: Serial numbers depending on design type

 Machine type Serial numbers Hand-operated machines from 1 to about 7000 Machines with electric motor from about 2000 to about 17000 Lever-set machines from 1 to about 7000 Keyboard machines from about 2000 to about 17000

These values largely correspond to the above allocation of years of production.

Dating based on the design type and the name of the manufacturer

Design and manufacturer's name give some hints for dating:

• Lever-set machines                                                    starting in 1896
• Keyboard machines                                                    starting in 1913
• Hand-operated machines                                          starting in 1896
• Machines with electric drive                                     starting in 1911
• Machines with double counter register                  starting in 1914
• Manufacturer name: Hans W. Egli, Zurich 2           to 1918
• Manufacturer name: H.W. Egli SA., Zurich 2       starting in 1918
• Keyboard setting check                                              starting in 1924
• Machines with multiplication keyboard                 starting in 1927

Remarks:
The introduction of the full keyboard machine (1913) enabled the development of a constant apparatus (design protection 1914). This additional device, described by F. Bühlmann in his 1915 essay, made the work in surveying considerably easier.

According to the Swiss official gazette of commerce No. 78 of April 3, 1918 (pages 534-535), the company H.W. Egli SA. was entered in the commercial register on March 30, 1918. It can therefore generally be assumed that machines with the Hans W. Egli name plate were manufactured by 29 March 1918 at the latest and machines with the H.W. Egli S.A. name plate by 30 March 1918 at the earliest.

Dating provided by selected museums

In the following section (see Tab. 8 to 30), an attempt is made to determine the construction period. Year of construction A reflects the information provided by the museum, while any additions such as circa were omitted. Year of construction B corresponds to the author's estimates. Red figures indicate deviations of 5 and more years from the values given in column B. Status of information on museums: 15 October 2018.

Since not all collection databases are publicly accessible or serial number or year of manufacture are missing, and for testing purposes a worldwide survey was carried out. It mainly relates to Europe, North America and Australia. In some cases, no responses were received by the editorial deadline, for example from Bletchley Park (National Museum of Computing), Bonn (Arithmeum), Solothurn (Museum Enter).

Preliminary remark

In several cases, 1895 is given as the year of production. The reason for this erroneous dating lies in a note which is engraved on certain machines:

PTD May 7TH 1895. Sept. 17TH 1895 (ptd = patented).

These misleading statements refer to two U.S. patents of Otto Steiger and have nothing to do with the year of construction.

The museums and collections are arranged alphabetically by country and within the countries alphabetically by place.

Australia

Tab. 8: Museum of Applied Arts & Sciences, Sidney

 Number Year of manufacture A Year of manufacture B 212 n.a. 1902 960 1895 1908 1077 1899 1909 1385 1880 to 1900 1910 1392 n.a. 1910 1829 1905 to 1915 1911

https://collection.maas.museum

Note:
Henry Ferdinand Halloran is said to have used No. 1077 from 1899 to 1950. This statement is incorrect.

Austria

Tab. 9: Technisches Museum Wien

 Number Year of manufacture A Year of manufacture B 1314 1900 1909 6480 1920 1927 9129 n.a. after 1928

http://www.technischesmuseum.at/online-sammlung/site/

Note:
The lever-set machine No. 1314 was manufactured by the sole proprietorship Hans W. Egli, the others by H.W. Egli SA. No. 6480 has a keyboard.

Tab. 10: Canada Science and Technology Museum, Ottawa

 Number Year of manufacture A Year of manufacture B 1902 1905 1911 2770 1910 1917

Note:
Both machines use setting levers for entering numbers.

Czechia

Tab. 11: Národní technické muzeum, Prag (National Technical Museum)

 Number Year of manufacture A Year of manufacture B 791 n.a. 1907 7558 n.a. after 1928

Note:
No. 791 works with setting levers, No. 7558 uses a keyboard.

France

Tab. 12: Musée des arts et métiers, Paris

 Number Year of manufacture A Year of manufacture B 2169 1895 to 1900 1913 10823 1925 to 1935 after 1928

http://cugnot.cnam.fr:8000/BASIS/collec/internet/objet/SF

Note:
No. 10823 has a second counter register. Such machines were available from 1914 onwards.

Germany

Tab. 13: Deutsches Technikmuseum, Berlin

 Number Year of manufacture A Year of manufacture B 310 1923 1905 9176 1899 to 1935 after 1928

Note:
The lever-set machine No. 310 bears the manufacturer's name Hans W. Egli. In 1918, the sole proprietorship was converted into H.W. Egli AG. No. 9176 has a keyboard. The manufacturer was H.W. Egli AG.

Tab. 14: Arithmeum, Bonn

 Number Year of manufacture A Year of manufacture B 10 n.a. 1896 73 n.a. 1898 1402 1904 1910 1846 n.a. 1911 2564 n.a. 1917 2950 n.a. 1918 7565 n.a. after 1928 9211 n.a. after 1928

Tab. 15: Private collection of Michael Lewin, Darmstadt

 Number Year of manufacture A Year of manufacture B 6 n.a. 1896 7 1898 1896 26 n.a. 1897 3431 n.a. 1920 9136 n.a. after 1928 10193 n.a. after 1928

Tab. 16: Deutsches Museum, Munich

 Number Year of manufacture A Year of manufacture B 1115 1909 1909 1160 1909 1909 10248 1895 after 1928

Note:
Machines with keyboard (No. 10248) appear as from 1913.

 Number Year of manufacture A Year of manufacture B 1712 1905 1911 2505 1900 1916 6046 1920 1923 6151 1920 1924

Italy

Tab. 18: Museo nazionale della scienza e della tecnologia "Leonardo da Vinci," Milan

 Number Year of manufacture A Year of manufacture B 2851 1911 to 1935 1918 3347 1913 to 1935 1920

http://www.museoscienza.org/dipartimenti/catalogo_collezioni/

Note:
No. 2851 is a lever-set machine. No. 3347 has a keyboard.

Netherlands

Tab. 19: Rijksmuseum Boerhaave, Leiden

 Number Year of manufacture A Year of manufacture B 4089 1895 to 1900 1921

Note:
Rijksmuseum means state museum.

Sweden

Tab. 20: Tekniska museet, Stockholm (National Museum of Science and Technology)

Number

Year of manufacture A

Year of manufacture B

1323

n.a.

1909

6346

1909 to 1911

1926

https://digitaltmuseum.se/

Note:
No. 6346 is a lever-set machine.

Switzerland

Tab. 21: Museum für Kommunikation, Berne

 Number Year of manufacture A Year of manufacture B 240 1904 1903 1520 1908 1910 3044 1912 1919 4062 1915 1921

http://datenbanksammlungen.mfk.ch/

Note:
No. 4062 is a keyboard machine.

Tab. 22: Musée de la machine à écrire, Lausanne

 Number Year of manufacture A Year of manufacture B 3230 n.a. 1919 6443 n.a. 1927

Note:
No. 6443 has a multiplication keyboard.

Tab. 23: Computermuseum Enter, Solothurn

 Number Year of manufacture A Year of manufacture B 1169 n.a. 1909 1680 n.a. 1911 2905 n.a. 1918 3066 n.a. 1919 4321 n.a. 1922

Tab. 24: Schweizerisches Nationalmuseum, Zurich

 Number Year of manufacture A Year of manufacture B 784 1895 1907 1377 1903 1910

https://www.nationalmuseum.ch/sammlung_online/

United Kingdom

Tab. 25: Science Museum, London

 Number Year of manufacture A Year of manufacture B 1382 n.a. 1910 2741 1914 1917 2918 1917 1918

https://collection.sciencemuseum.org.uk/search?q=millionaire

USA

Tab. 26: Harvard University, Cambridge, Massachusetts

 Number Year of manufacture A Year of manufacture B 240 1900 1903 704 1900 to 1910 1907 3282 1925 1920 6215 1915 1924

http://waywiser.fas.harvard.edu/collections

Notes:
The No. 240 and 704 have setting levers and a Hans W. Egli name tag. The No. 3282 and 6215 offer a keyboard and carry a name tag with H.W. Egli SA.

Tab. 27: MIT Museum, Cambridge, Massachusetts

 Number Year of manufacture A Year of manufacture B 1030 n.a. 1908 1637 n.a. 1911 2653 n.a. 1917 3177 n.a. 1919

https://webmuseum.mit.edu/main.php?module=objects

Notes:
No. 3177 has a keyboard, the other machines use setting levers. No. 2653 is motor-driven.

Tab. 28: Yale University, New Haven, Connecticut

Number

Year of manufacture A

Year of manufacture B

3086

n.a.

1919

9104

n.a.

after 1928

https://www.yale.edu/research-collections/museums-galleries

Tab. 29: Computer History Museum, Mountain View, California

 Number Year of manufacture A Year of manufacture B 272 1895 1904 539 1930 1906 990 1895 1908 1073 1910 1909 4493 1895 1922 6417 1895 1926

http://www.computerhistory.org/collections/search/?s=millionaire&f=physicalobject

Notes:
The museum has taken over the Gwen Bell artifact and book collection. No. 272, 539 and 1073 use setting sliders. The machines 4493 and 6417 are electromechanical devices; such models with electric motors were introduced in 1911. Gordon Bell's website, on the other hand, mentions the following production years: 1900 (No. 272), 1903 (No. 539), 1920 (No. 4493). There is another machine listed: No. 1523 (1910).

Tab. 30: National Museum of American History, Washington, D.C.

 Number Year of manufacture A Year of manufacture B 809 1904 1907 821 1904 1907 832 1904 1908 837 1904 1908 1132 1906 1909 2432 1909 1916 2609 1909 1917 4154 1914 1921 9123 1928 after 1928 14382 1935 after 1928

http://collections.si.edu/search/

In the case of the Millionaire, the numbers were entered either using setting levers or a keyboard (see Fig. 3). The machines worked with a crank or an electric motor.

Fig. 3: This well-preserved, about 100-year-old manually operated Millionaire is fully functional.
On the left in the picture the multiplication lever, on the right the 8-digit full keyboard,
whose settings can be cleared with the round buttons (front).
Credit: Historisches Museum Thurgau, Schloss Frauenfeld

Further Collections
The year data are approximate.

Germany

• The lever-set machine of the Technoseum in Mannheim with No. 3376 was probably built in 1920. The museum dates it to 1927.

Switzerland

• The cantonal Vermessungsamt in Aarau has a lever-set machine in a wooden housing with the No. 1464. It dates back to about 1910.
• The Millionaire of the Vermessungsamt of the city of Bern has the No. 17523. It was probably made after 1928.
• The keyboard machine of the Amt für Landwirtschaft und Geomatik in Chur bears the serial number 12989. It was probably manufactured after 1928.
• The Historisches Museum Thurgau (Schloss Frauenfeld) has a mechanical Millionaire with a full keyboard. It bears the No. 3265 and was probably built around 1920.
• The machine of the Schreibmaschinenmuseum Beck in Pfäffikon ZH with the serial number 1379 was made about 1910.
• The Millionaire No. 2261 of the Abteilung Vermessung of the city of St. Gallen was built around 1914.
• The Abteilung Amtliche Vermessung of the City of Zurich has a keyboard machine No. 3260 (about 1920). It is equipped with a constant apparatus.
• Swiss private collections include the following machines: in Buchs SG No. 3253 (1919), Davos GR No. 6082 (1923), Gelterkinden BL No. 2547 (1916) and 4007 (1921), Kienberg SO No. 6290 (1925), Lenzerheide GR No. 4372 (1922), Männedorf ZH No. 915 (1908), Yens VD No. 2943 (1918).

USA

• The Millionaire of the IBM corporate archive in Poughkeepsie, NY, with the number 403, dates back to about 1905.
• The Museum of Science and Industry in Chicago has a machine No. 10240, which was probably sold after 1928.

Milestones in Analog and Digital Computing

A detailed description of the H.W. Egli SA, Zurich, as well as of the Millionaire and Madas calculating machines (with step-by-step operating instructions for both devices) can be found in the following two-volume book (see Figs. 4 and 5):

• Herbert Bruderer Meilensteine der Rechentechnik. Band 1: Mechanische Rechenmaschinen, Rechenschieber, historische Automaten und wissenschaftliche Instrumente, 2., völlig neu bearbeitete und stark erweiterte Auflage, Walter de Gruyter GmbH, Berlin/Boston 2018, XXIV, 727 Seiten (Milestones in Analog and Digital Computing. Volume 1: Mechanical calculating machines, slide rules, historical automatons and scientific instruments, 2nd, completely revised and geatly enlarged edition, Walter de Gruyter GmbH, Berlin/Boston 2018, xxiv, 727 pages)
• Herbert Bruderer: Meilensteine der Rechentechnik. Band 2: Erfindung des Computers, Elektronenrechner, Entwicklungen in Deutschland, England und der Schweiz, 2., völlig neu bearbeitete und stark erweiterte Auflage, Walter de Gruyter GmbH, Berlin/Boston 2018, XX, 829 Seiten (Milestones in Analog and Digital Computing. Volume 2: Invention of the computer, electronic computers, developments in Germany, Great Britain and Switzerland, 2nd, completely revised and greatly enlarged edition, Walter de Gruyter GmbH, Berlin/Boston 2018, xx, 829 pages)

Fig. 4: Cover picture of volume 1 of the "Meilensteine der Rechentechnik"
with Sauter cylindrical calculator.
Credit: De Gruyter, Berlin/City museum Göteborg

Fig. 5: Cover picture of volume 2 of the "Meilensteine der Rechentechnik"
with Turing-Welchman bombe.
Credit: De Gruyter, Berlin/National Museum of Computing, Bletchley Park

Meilensteine der Rechentechnik (Milestones in Analog and Digital Computing), vol. 1

https://www.degruyter.com/view/product/480555

Meilensteine der Rechentechnik (Milestones in Analog and Digital Computing), vol. 2

https://www.degruyter.com/view/product/503373

Acknowledgements

Countless people took part in this investigation. The author would like to thank the following persons for their information and hopes not to have forgotten anyone:

Stefan Beck, Gordon Bell, Peter Benz, Monica Bilfinger, Gian-Luca Bona, Christian Burchard, Monica Bussmann, Max Campbell, Carola Dahlke, Urs Darnuzer, Deborah Douglas, Gallus Erne, Stéphane Fischer, Bruno Fricker, Roland Gross, Michael Hagmann, Kurt Hofmann, Walter Hollinger, Vincenzo Iannone, Juri Jaquemet, Urs Kälin, Michael S. Kelley, Peggy Kidwell, Thomas Kosche, Nicolas Krocker, Karl Kronig, Eva Kudrass, Aldo Lardelli, Hansjörg Leimer, Michael Lewin, Hans-Andrea Loeliger, Martin Lüpold, Urs Meier, Otmar Moritsch, Peter Muckermann, Marco Nold, David Pantalony, Jacques Perrier, Oliver Plüss, Corinne Raczyniski, Paola Redemagni, Mirjam Rösli, Gérald Saudan, Marcel Sax, Franziska Schärli, Hans Peter Schaub, Ulrike Schelling, Gérard Schmid, Barbara Schmutz, Alexandra Schneider, Bernard A. Schüle, Nadine Schwald, André Sigel, Stefan Stein, Elsbeth und Walter Strässler, Christine Süry, Antonín Švejda, Gerdine van den Dool, Stefan Walter, Adrian Whicher, Doug Zimmer.

References

• Bühlmann, F.: Die Berechnung der Koordinaten der Grenzpunkte mit der Rechenmaschine „Millionär", in: Schweizerische Geometer-Zeitung, volume 13, 1915, issue 6, pages 154–164
• H. W. Egli AG (Hbt./hh): 50 Jahre Egli-Rechenmaschinen. Entwurf zu einer Jubiläumsschrift, Zürich 1943, 13 pages (typewritten, Hbt. probably stands for Herbert Bannwart), Museum für Kommunikation, Berne, Pap 1734
• H. W. Egli AG. Rechenmaschinenfabrik, Seestraße 356/358, Zürich-Wollishofen, gegründet 1893, 2 pages, circa 1943, Museum für Kommunikation, Berne, Pap 1734
• Total v. H.W. Egli AG produzierte Rechenmaschinen (vom Anfang bis zur Liquidation), um 1972, 1 page (handwritten), Museum für Kommunikation, Berne, Pap 1734
• Rechenmaschinen geliefert bis Jan. 1942, 1 page (handwritten), Museum für Kommunikation, Berne, Pap 1734
• Daten aus der Geschichte der Firmen Hans W. Egli und H.W. Egli A.G., Zürich-Wollishofen, circa 1961) (11/10/611 RK-; copy of Hbt), 2 pages (typewritten), Museum für Kommunikation, Berne, Pap 1734
• Haarpaintner, Adolf: Entwicklungsgang der Rechenmaschine „Millionär", Zürich, 7. Oktober 1933, 15 pages (handwritten), Museum für Kommunikation, Berne, Pap 1734
• Haarpaintner, Adolf: Zusammenstellung aller Sorten der fabrizierten „Millionär", 7. Oktober 1933, 1 page (handwritten), Museum für Kommunikation, Berne, Pap 1734
• Lewin, Michael: Entwicklungsgeschichte der Rechenmaschinen der Firma H.W. Egli bis 1931, in: Typenkorb 1992, issue 48, pages 15–20
• Lewin, Michael: Entwicklungsgeschichte der Rechenmaschinen der Firma H.W. Egli bis 1931, in: Typenkorb 1992, issue 49, pages 6–12
• Register of Millionaire calculators, John Wolff's web museum (http://johnwolff.id.au/calculators/Egli/Register/MillionaireRegister.htm)
• Saudan, Gérald: Swiss calculating machines. H. W. Egli A.-G. – A success story, Yens sur Morges VD 2017, 147 pages (self-published)
• Sossna, H.: Auflösung der Aufgabe des Einkettens mittelst Maschine und numerisch-trigonometrischer Tafel. Die neue Multiplicationsmaschine von Otto Steiger und Hans W. Egli in Zürich, in: Zeitschrift für Vermessungswesen, volume 28, 1899, issue 24 , pages 665–696

To whom it may concern

The author is very grateful for further references to preserved Millionaire calculating machines, if possible with serial number, manufacturer name, additional details and photos.

Herbert Bruderer is a retired lecturer in didactics of computer science at ETH Zürich. More recently, he has been an historian of technology.
[email protected], [email protected]