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Hollerith Census Machine

Manufacturer Hollerith
Replica manufactured by Roberto Guatelli for The Computer Museum.
Identification,ID XD231.81
Date of first manufactureabout 1890 - (replica - 1981)
Number produced ? - (replica - 1)
Estimated price or cost-
location in museum -
donor Digital Equipment Corp.

Contents of this page:

  • Hollerith replica - 110 K Bytes
  • card reader, sorter from patent
  • Hollerith card punch courtesy of Computer History Museum
  • Placard

    Electrically driven card reader and 40 dial accumulators, with provision for signal to be sent to open a door in the sorter.

    The card reader was an array of spring loaded pins that would individually sense a potentially punched hole by passing through the hole, into a small pool of mercury, completing an electrical circuit.

    The machine could be wired to use that individual electric current to increment one of the 40 dial accumulators, and/or open the door of one of the sorter pockets.

    The processed (read) card could be easily, reliably placed in the automatically opened door.

    Special features
    The sorter mentioned above provided for selection of cards for further types of counting and analysis in further passes of the cards through the system. An example could be sorting in pass 1 could be by country of origin, then on pass 2, the system could count those of each country of origin by state of current residence. This provides a great deal of flexibility in processing and analysis.

    There is a question about the electrical current that was used to power this machine. Carbon/zinc primary batteries were commercially available, and Mr. Edison's electric light and power systems were becoming available (in some cities). Both were direct current. Which was in use? What voltage?

    Historical Notes
    A discussion of Herman Hollerith and sorting in general by Donald Knuth

    There are no known original Hollerith census machines. This machine is a replica.

    Hollerith had earlier considered using wide paper tape, with many records per length of tape, but the potential problems of tape damage, and difficulty of finding particular records, and well as inability to sort on particular characteristics discouraged further consideration of the paper tape idea. The punched cards of the Jacquard loom operation promised better operation. (The cards of the Jacquard loom were physically connected to insure correct serial operation. Hollerith cards were not physically connected.)

    The story that the Hollerith card was the identical size as the then current U.S. dollar to provide an easy source of storage drawers seems correct.

    An early Hollerith card had 24 columns and 12 rows of possible round holes. The was column count was later increased to 80 columns of narrower rectangular holes.

    The Hollerith Census Machines were a "second generation" of successful machines used in 1887 to tabulate mortality statistics in New Jersey and New York City.

    e-mail from Yellow Airplane who suggests this link to U.S. Census Bureau.
    (The U.S. Census Bureau bought UNIVAC 1, serial # 1. One of a series replacements for the 1890s Hollerith machines.)
    ----- Original Message -----
    From: "Len Shustek" 
    Subject: Re: Univac 1 SN 001 plaque
    > George:
    > I'm chairman of the Board of Trustees of the Computer History Museum, 
    > and I echo John Toole's and Grant Saviers' interest in collaborating 
    > with you, especially insofar as the history of the Census Bureau 
    > overlaps the history of computing.
    > One thing that puzzles me, though, is how the Census Bureau can only 
    > be celebrating it's 100th anniversary if we've been doing the census 
    > since 1790.  Even the Bureau's web site page on their own history
    > ( talks about activity 
    > in the 1800's, and doesn't mention anything significant happening 
    > in 1902.  From the perspective on computer history, 
    > the important dates are 1890 (for the introduction of the Hollerith 
    > machine, leading to IBM), and 1950 (for the use of the Univac).  
    > Is there a better place to look for the history of the Bureau?
    > Len Shustek
    Hi Len. Thank you for your welcome reply.

    You are correct that there have been national population censuses taken since 1790 and every ten years thereafter. However, that first census was undertaken under the auspices of the State Department (headed at the time by Thomas Jefferson), and conducted by U.S. Marhsals.

    Subsequent censuses were conducted under the auspices of the State Department, the Department of the Interior, and the Commerce Department. It was not until March 6, 1902, that legislation was passed to create a Census Bureau, a full-time, year round agency. Prior to that, it had been the Census Office and was located in several different places.

    Further, it was not until July 1, 1902, that the U.S. Census Bureau literally opened its front doors. In fact, on or about July 1, 2002, there will be additional festivities taking place in Suitland.

    I hope you and your colleagues will be able to attend. I am very excited about the prospect of working together on this, and will present the information you and your colleagues from the Computer History Museum have sent.

    As to a better place to look for information about the Bureau's history, there are several publications available including one written by ex-director, A. Ross Eckler, called "The Bureau of the Census."

    Plus, I am about to complete a Centennial Planner that documents much of the Bureau's history and technological achievements. It includes anecdotal information, a timeline, and historical photos. I'll see to it that you all receive copies.

    I am scheduled to meet with the Census Bureau's Centennial Committee on Monday afternoon, and feel certain that this news will be greeted with a most positive reaction.

    Thank you again, and I look forward to hearing from you soon.


    George Selby, Manager
    Marketing Services Office
    U.S. Census Bureau
    4700 Silver Hill Road
    Suitland, Maryland 20746

    This Specimen
    • Replica commissioned by Digital Equipment Corp. (DEC)

      E-Mail to Dag Spicer from Gwen Bell May 11, 2000
      We got permission from IBM to use Guatelli and DEC paid for the replica. (That was at a time that the division between DEC and the Museum was not clear.) When the division came, then we ended up with the replicas.

      While Guatelli was an independent businessman probably 75% of his income came from IBM. DEC could not take over this role and IBM had made it possible for Guatelli to work for clients like the Government of Italy. Fortunately they gave their permission. Gwen

      Yes, the donor was DEC. But that was a time when the line between the Museum and DEC did not exist. Since the Museum was a part of DEC that was meant to spin off, then the object can simply say "manufactured by Roberto Guatelli for The Computer Museum." That is totally true, (and probably meaningless to most folks.) But IBM cannot object.
      The bottom line is that this is great to have in terms of telling the story of the history of computers.
      Close examination of this replica shows that much internal wiring was not replicated.

      In June 2017, Carl Claunch examined an original machine in the Endicott History and Heritage Center and reports that there was a (not removable) plugboard in the back of the machine which allowed wiring of individual card reader contacts to individual counters. It is quite possible that this same plugboard could be wired to open a selected sorter door.

    Interesting Web Sites

    Other information
    from Silvio Hénin, December 13, 2019
    Dear Mr. Strickland,

    recently I came through your papers “Roberto Guatelli. Who was that Guy?” (; CHM Volunteers Information Exchange, 2012).

    I am an Italian scholar of the history of technology and I am trying to reconstruct Guatelli’s life and works. For this purpose, I am collecting information from museums, newspapers, and historians all over the world, but there are still many gaps to be filled. One is the beginning of Guatelli’s business in 1946-50, when he came back from Japan: how did he start?, with which money? The other is the period after 1961, when he left IBM and established his own business: did he produce other replicas ? For whom?

    The more important question is: where all those objects are now?

    Did you interview Guatelli himself or Joseph Mirabella? Have you more information?

    From what I have already received and examined, it seems that Guatelli was a bit ‘boaster’. One for all: he was not the author of 1939 models exhibited in Milan (1939) and in New York (1940). In fact he was hired just to take care of the shipment of the pre-war collection of Leonardo models and to accompany it in the US and Japan. His first Leonardo’s replicas were built in New York and Los Angeles in 1947-48. At best they are journalistic exaggerations or misunderstandings, Guatelli spoke a little English at that time.

    I thank you in advance for any hint or clue you can give me.

    Silvio Hénin
    Milan (Italy)

    from Silvio Hénin, December 16, 2019

    I became interested in Roberto A. Guatelli’s life and works after reading the story of the presumed Leonardo da Vinci’s calculator the Italian craftsman built in 1967-68 for IBM. (E. Kaplan, “The Controversial Replica of Leonardo da Vinci’s Adding Machine”, 19(2), 1997, pp. 62-63.). My interest grew when I discovered that several model of ancient calculating machines, now scattered in many museums all around the world, were made by Guatelli when he was hired by Thomas Watson, Sr. and afterward, when he started an independent business. Finding Strickland’s short biography gave me a point to begin with. Thanks to the kind answers of museums, and historians, to newspaper articles and old catalogues, I recently found many more pieces of information and I am putting them together, like a puzzle. Still there are many gaps I hope to fill in the near future.

    There is something in Strickland’s and other stories already published, that deserves to be commented. First of all, Roberto Guatelli never graduated in engineering, h e didn't even go to university. There is no evidence that he started building Leonardo’s models in the ‘30s and certainly he did not build the models exhibited in Milan (Italy) in 1939, New York (1940) and Tokyo (1942). He was not appointed by the fascist government to organize the Milan exhibition, but was just commissioned to accompany it in New York and Tokyo, and to take care of its maintenance (M. Beretta, E. Canadelli, C. Giorgione (eds.), Leonardo 39 , Editrice Bibliografica, 2019). Moreover, when he left for Japan, Italy was still not at war with the US, in fact he asked to remain in America, but was ordered by the Italian government to go to Japan.

    While he was in Tokyo the war between USA and Japan broke out. Thus, it was not possible for him to return neither in America nor in Italy (it was too dangerous and almost impossible). After September 8, 1943 (armistice between the Allies and Italy) most Italian residents in Japan were rounded up and interned in a concentration camp. Not so Guatelli who
    enjoyed a certain freedom, probably thanks to the acquaintances he made in Tokyo. When the American forces occupied Japan, Guatelli asked SCAP (Supreme Command of Allied Powers) to return in America, instead of Italy.

    He was granted a visa and he reached New York, married and started his business building more than sixty new Leonardo’s models (on the basis of the 1939 blueprints he retained, which were not his own) to be sold or rent to museums and private collections. In the meantime, Guatelli created his own myth, with the help of journalists and admirers, widespread by magazines and newspapers. The first exhibition was in 1949 at the Los Angeles County Museum, followed by Dallas, Denver and Dearborn (1950), to end in Pittsburgh. In 1951 Thomas Watson Sr. (I haven’t found any reference to Eleanor Roosevelt) bought the collection and hired him to build other replica for IBM, not only Leonardo’s machines, but also other ancient calculators and devices.

    The rest of this story is better known, but what still remains to be completed is the fate of the rich IBM collection and other Guatelli’s manufacts. See for instance two recent papers by Herbert Bruderer: “ The Model Maker of Leonardo da Vinci, Blaise Pascal, and Charles Babbage” ( and “ More Replicas of Historical Calculating Machines Found” (

    Silvio Hénin

    December 16, 2019

    "RESURRECTION" Number 86 - Summer 2019
    a publication of the (British) Computer Conservation Society
    "CCS Visit to NAM-IP at Namur", Namur, the capital city of the Wallonia region of Belgium
    "The Museum houses an original Hollerith machine from the 1880s, one of just four still in existence worldwide. ... "

    click to enlarge

    from Pamela McCorduck March 17,2001

    Guatelli [the builder of this replica] was fascinated by da Vinci's machines (or rather, the plans for them) and built a few--the bicycle, a kind of flying machine, some other objects. This was in the thirties, and when they went on exhibit, Mussolini was so pleased with this great example of Italian engineering heritage that he decided to fund a traveling exhibit to impress his gallant Axis allies in Japan, which is how Guatelli and his models went to Japan.

    The war suddenly intervened, and Guatelli couldn't get back to Italy, much less anyplace else. He stayed in Japan until war's end, and then somehow made the acquaintance of T. J. Watson, Sr., who recognized his genius for building, and commissioned him to do some replicas of very early computation machines. Watson was instrumental in bringing Guatelli to the U.S., where Guatelli set up a small workshop on Lafayette Street in NYC, where he built many things for IBM.

    He really was superb at what he did.

    from Jim Strickland

    Roberto Guatelli - Who Was that Guy?

    Jim Strickland

    We don't have many replicas in CHM and the ones that we have are very good and they help tell the computing history story. One that really makes its gallery is the Hollerith tabulator and sorter replica, the icon of the punched card gallery. It was made by Roberto Guatelli. Recently, I came to realize that the same man made the Pascaline replica and the Babbage Difference Engine No. 1 replica. both in the calculator gallery. So who was that guy Guatelli and how did he come to make those wonderful replicas?

    It's a fascinating story.

    Roberto Guatelli was born in 1904 and educated as an engineer. Early in his career he became interested in the machines of Leonardo da Vinci or rather he became fascinated with da Vinci's drawings of machines. Guatelli lived in Milan where Leonardo had done much of his work. In the early 30's he began to build models or replicas from da Vinci's drawings -- a bicycle. a kind of flying machine, some other objects. When they went on exhibit, Italian dictator Benito Mussolini was so pleased with this great example of Italy's engineering heritage that he decided to fund a traveling exhibition to impress the world. Guatelli and his exhibition were in the US when World War II broke out. As an Italian, the US declared him to be an enemy of the US. Traveling to Italy was too dangerous at that time, so he was deported to Japan.

    Italy and Japan were part of the Axis Powers but Japan reacted with outrage to the surrender of Italy to the Allied forces in September 1943. Italian citizens residing in Japan were rounded up and asked whether they were loyal to the King of Savoy, who had dishonored Japan by surrendering to the enemy, or to Mussolini and the newly created "Repubblica Sociale Italians", which vowed to continue fighting alongside the Nazis. Guatelli and others who sided with the King were interned in concentration camps and detained in dismal conditions until the end of the war. His models were destroyed when the warehouse where they were stored was bombed.

    After the war, Guatelli began rebuilding his models. In 1947 he had an exhibition at the Ford museum in Dearborn, Michigan. Eleanor Roosevelt, who was visiting the museum introduced Guatelli to Thomas Watson Sr. who was also visiting. Thomas Watson recognized Guatelli's genius and hired him in 1951 to rebuild more of his models for IBM which then toured them as a corporate sponsored exhibition. (The exhibit, now 16 models. still tours and is currently being shown at The Yager Museum of Art and Culture at Hartwick College in Oneonta, NY.)

    Guatelli worked for IBM until 1961. He had a workshop in the basement of IBM's World Headquarters at 590 Madison Avenue. In 1962, he left IBM and opened a small workshop on Lafayette Street in New York City. In 1964, his stepson JosephMirabella joined the firm.

    Dr. Guatelli demonstrating one of his models
    A machanical version of today 's massive hydro-electric plants is the da Vinci grinding mill shown above. A set of grinding machines, seen at right, was placed on each bank of a swiftly moving stream. Power was furnished b a series of water wheels, shown at left, located in midstream and connected to the grinding weights by a system of shafts and gears.

    Watson owned an original Pascaline, the 17`° century adding machine invented by Blaise Pascal. In the late 1960's, Watson wanted a replica of the machine that could be moved and exhibited. Guatelli and Mirabella made it for him and they made three other replicas. Mirabella recalled the difficulty they had achieving the patina of the machine. But when they were done, IBM could not tell the difference between the original and the replicas. Like the original, the replicas had great difficulty adding to 1,000. The mechanism as designed could not move the gears beyond 999. Over time. they made a few other replicas which IBM presented as gifts to executives.

    In 1972, they made the model of Babbage's Difference Engine #1 prototype for IBM which was presented to retiring chairman T. V. Learson. It is now displayed in the CHM Calculators gallery, courtesy of Mr. Learson's wife. They also made a second replica.

    In 1974-75, IBM commissioned a Hollerith machine replica for a touring exhibition. It was based on an original machine in IBM's collection. In making the replica, they also re-built the original to working condition.

    (Also. in our collection we have a Guatelli model of the Leibnitz "stepped drum" as used in the Leibnitz calculator and a demonstration model of a single digit carry mechanism from the Schickard calculator.)

    While Guatelli and Mirabella worked primarily for IBM. they had other clients. In 1981, Digital Equipment commissioned a Hollerith replica for its nascent computer museum. That is the replica that we have. They also made a Pascaline replica for DEC's museum.

    Mirabella believes that the firm made six or eight Pascaline replicas, just two of the Difference Engine replicas and four to six Hollerith tabulator replicas.

    Roberto Guatelli died in September 1993 at the age 89. The work shop in New York, run at the time by Mirabella, closed in 2005. Nathan Myhrvold bought the remaining calculating replicas and Mirabella donated the Leonardo models to the Suffolk and Riverside Science Museum in New York.

    Replicas help us tell the story, and the replicas made by Roberto Guatelli and Joseph Mirabella are works of technology and art in their own right.

    also from Jim Strickland

    click to enlarge

    If you have comments or suggestions,
    Send e-mail to Ed Thelen. Go to Antique Computer home page
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    Updated Dec 13, 2019