The version shown here is a first edition from 1895, when the Comptometer still had a wooden case and only one key could be pressed at a time. My copy has a library stamp on the front cover that says "Library U.S. Patent Office, Nov 29 1896", and inside is written in pen "Writen by D.E. Felt.". The page that describes oiling of the mechanism has been stamped with the text "Oiler given when Comptometer is billed". This may refer to the small oil can shown in the Paraphernalia section.

This is the 1911 edition of the standard manual for using the Comptometer. It has now expanded to 58 pages, though it tackles exactly the same set of subjects. This version is from just before the "Controlled-Key" mechanism was introduced, so the illustrations and photos use the model B or C Comptometer.

Note the presence of the shield logo - a shield with the symbols of the four arithmetic operations on it, with Comptometer written across the top. This logo would often be used in printed material, as well as the rings and badges, but never on the Comptometer machines themselves, and rarely in advertising.

This is the 1921 edition of the above standard manual for using the Comptometer. It has now expanded to 67 pages, mostly by having additional pages inserted at the start before the main text. These pages deal with oiling, the Controlled-Key mechanism and error correction, and the features of the clearing mechanism of the model H.

This is the 1928 and probably final edition of the above standard manual for using the Comptometer. It is almost the same as the 1921 edition - just a few pages have been rewritten, and it runs to only one more page than before. References to the model H have been updated to the model J.

This booklet is a Dutch manual for the Comptometer. It is a shortened version of the Methods of Operating the Comptometer booklet above, leaving out the directions for oiling and the more advanced calculation techniques. It explains the "Controlled-Key" mechanism, addition, multiplication, subtraction, and division.

The illustrations in the booklet show the model F Comptometer. There is no publication year inside, but it probably dates from 1919 or 1920 because it says that the Dutch office of Felt & Tarrant was in Amsterdam, Koningsplein 1. From phone books and newspaper ads I found the successive addresses of their office and the dates they resided there:

1909-1919	Damrak 28-30, Amsterdam	Move took place on 1st May 1919
1919-1931	Koningsplein 1, Amsterdam
1932-1943	Prins Hendrikkade 20, Amsterdam
1946-1950	Rokin 84, Amsterdam

They kept the same telephone number throughout, apart from the addition of a digit when the telephone exchange was upgraded.

This booklet is a French manual for the Comptometer. It is a translation of the Methods of Operating the Comptometer booklet above, even including the sections on British currency and Imperial weights.

There is no publication year inside, but it probably dates from 1915-1920, as the illustrations show the model F Comptometer. It included a card with a further explanation of how to use the Controlled-Key mechanism and correcting errors.

This thin booklet has no copyright year, and strangely does not mention the company Felt and Tarrant anywhere. The version shown here is from approximately 1915. Its title is listed in The 1911 Register Of Copyright Entries, and while the text is probably from that year, the pictures on the front and inside have been updated to show a model E, and a picture on the back shows a model F. A small card was included to explain the Controlled-Key mechanism and error correction. A French version of that card can be seen above that was included with "Méthode Pour Opérer"

This is the 1920 version of the above booklet, which is a simplified manual for using the Comptometer. It has now been expanded to explain the "Controlled-Key" mechanism. At the end it has a list of the various tables that were available, some of which you can find in the Tables section of my collection.

This is the British version of the above 1920s booklet. Unfortunately it is missing its front and back covers. The contents of many pages are virtually identical to the American version apart from the photographs which now feature a Comptometer with a keyboard for British Currency, but a few pages of the American version have been omitted to make room for instructions about handling currency correctly.

This version has no copyright year, but shows the model H or J on the first page. It could date anywhere from about 1921 to 1934, but I guess it is from 1930, and that this is the first version that was used as the new simplified standard manual, replacing the final 1928 version of "Methods of Operating the Comptometer". All the later versions use the same design for the front cover, apart from the colour.

This version is from the 1940s, possibly 1941, but there is no publication year inside. The first page shows the model K and model M. It has 19 pages plus 3 pages of tables.

This is the 1958 edition. It is virtually identical to the 1940s edition, except that all photographs and drawings were updated to new models, and the page about the Controlled-Key (now the Accuracy Key) has been rewritten.

One interesting change is the claim in the introduction that there are now eight different standard sizes of comptometer. Whereas there used to be only 8, 10, 12 column keyboards as standard, with a 20 column version for special statistical work, there are now apparently also 5, 7, 9, and 11 column versions. The Customatic shown in the photo on that page does have 9 columns.

This is an Italian version of "Easy Instructions for operating the Controlled-Key Comptometer". There is no publication year inside, but it is probably from between 1950 and 1956 as the first page shows the models 992 and 3D11. It has 19 pages plus 3 pages of tables.

This book opens vertically, like a notebook. It has 195 pages - pages 1 to 96 on one side, and then turn it over to get pages 97 to 195. It contains a great many exercises, with which to practice working on the Comptometer.
In my copy of the book, many of the pages have answers penciled in. The front flyleaf is inscribed "Maxine Fick, 5069 N Damen Ave., Chicago, Ill." with the telephone number "Ravenswood 2264". At the time of the 1930 US census she was 13 years old. Underneath is written "Bryant & Stratton College, 18 S. Michigan", which is a chain of business schools. I found an online image of an advert for this school from 1937.

This is the 1954 edition of the book. It opens vertically, like a notebook. It has 304 pages - Part One consisting of pages 1 to 152 is on one side, and if you turn it over you have Part Two, also with pages numbered 1 to 152. It contains a great many exercises, with which to practice working on the Comptometer. It covers the same subjects as the previous editions, but in a less terse manner.
My copy of the book is in good condition, and only a few of the pages have answers lightly penciled in.

This book contains all the answers to the calculation exercises in "The Comptometer Course for Business Training". It has no copyright year and is hard to date exactly, but its lettering on the cover matches that of the 1954 edition above. The original owner has written their name and address on the inside of the back cover: "Property of Lottie Marche, 7132 S. Glengarry Ave, Whittier, Calif.".

This is the 1963 edition of the book, published after Felt & Tarrant were bought by Victor Business Machines. It has been completely rewritten, and has shortened to 176 pages. Many pages of the book are perforated so that part of the page can be filled in and handed in to the teacher for marking. The list of Comptometer models includes not just the former Felt & Tarrant models, but also various Bell Punch Sumlock models that were imported and rebranded as Victor Comptometers.

My copy of the book is in good condition, and only a few of the pages have answers lightly penciled in. The front cover has the name "Willa Hale" written on it, as does the receipt I found in the book which shows it was bought for $3.50 in 1965.

This book contains all the answers to the calculation exercises in "The Comptometer Course for Business Training", including the Review Tests. It has no copyright year, but it belongs to the 1963 edition above so it is presumably also from that year.

The pages in this envelope are the final Review Tests for the Comptometer Course for Business Training. The envelope itself has a student grade card printed in one side, and on the other side a table for calculating the grades from the number of correct answers on any test. There is no copyright year, but the tests belong to the 1963 edition above so they are presumably also from that year. The envelope seems to be older as it uses a different form number, so may have been printed in the Felt & Tarrant era.

This instruction book was used at Felt & Tarrant Comptometer schools. It consists of 32 leaves of thick paper printed on only one side, and bound at the top edge by two metal rings. It covers the basics of arithmetic in 14 lessons, and it would take about 13 days to teach. According to its table of contents, there were about five more similar course books to follow for the full 3-month course. It may be that the original owner of this manual followed only the short introductory course.

My copy of this book has the name Gene Fleming written on the front, and some of the answers have been filled in.

When a company bought one or more Comptometers, as a courtesy Felt & Tarrant would offer to train some of the company's staff in the use of the Comptometer. This course book was used for such a training course. It covers the basic methods of performing arithmetic in great detail, and includes practise exercises along the way.

This book goes into great detail how the Comptometer can be used in various business processes. Mine has the name "Miss Ideus" written on the first page. The book contains prints of several photographs showing the Comptometer being used in the workplace. Pictures of most of those pages can be seen below.

A complete scan of the 1914 edition is available from the Internet Archive, available as a pdf file and in many other formats.

This booklet contains a table for calculating cube roots. There are 2 pages of instruction, followed by the table on 10 pages.

The table consists of two columns of entries for the numbers 1 to 1000. The first column gives n³-(n-1)³, the second column gives n³-t³ where t is nearest multiple of ten that is strictly less than n. The instructions explain how you can use the second column to get an integer cube root of up to 3 digits, and how to use the first column to calculate up to 3 digits after the decimal point.

This booklet contains a table with the decimal expansions of 1/n for n up to 10,000. There are 10 pages of introduction, followed by the table on 40 pages which are tabbed for quick access. It has a sturdy cardboard cover, slightly larger than the pages.

Although the text has a copyright of 1917, the version shown here was printed in the 1940s because the title page has a picture of the model M, and the cover mentions the Comptometer Division of Felt and Tarrant. The 1917 version has the longer subtitle "to Be Used in Connection with the Controlled Key Comptometer Adding and Calculating Machine".

There are three minor mistakes in the table. The reciprocals for 118, 185, and 476 were erroneously rounded up instead of down in the last decimal. These errors may have been deliberately introduced as copyright traps to recognise illegal reproductions.

This small spiral-bound exercise book has thick cardboard covers and contains 78 pages which each have a single column of numbers to be added using the Comptometer. It shows no copyright year, but the form number and the picture of a model H mean it probably dates from the early 1920s.

This comb-bound exercise book has thick cardboard covers and contains 1 page of text followed by 393 sums to be done on the Comptometer.

This booklet with exercises came with the Comptometer Educator (see the Paraphernalia section). I don't know its year of publication, but it is probably some time in the late 1940s or early 1950s.

In the mid-1950s Felt & Tarrant diversified by manufacturing a dictation machine. The recording medium was a wide Mylar belt of magnetic tape, called the Erase-O-Matic magnetic belt, which allowed for quick access to any part of the recording just by moving the tape head sideways. This leaflet contains the instructions.

This is the Italian translation of the above leaflet "Instructions for operating the Comptometer dictation machine". It does not contain the illustrations, just the text, so it is only 4 pages long.

This small book was published by Felt & Tarrant and given for free to American soldiers to aid them in the Great War. It contains words and phrases that are supposedly useful to a soldier in France, though for many there was unlikely to have been any opportunity to put them to use. Near the back there is an advert for the Comptometer, described as "the Machine Gun of the Office". The first page says:

In the hope that it may prove a convenient and serviceable aid to the intelligible expression in French of words and phrases necessary to communicate the common wants, wishes and desires of everyday military and social life, this French Phrase Book is presented to the soldier boys of America
with the complements of
Felt & Tarrant Mfg. Co.
Chicago

This book has a name written on the inside cover in pencil, "Wilburn C Buttler, Ft. Worth". The closest match is from the 1920 census - Wilburn C. Butler, in Fort Worth (Ward 11), Tarrant County, Texas. He was born on 8 October 1888, died on 3 April 1955, and is buried in Mount Olivet Cemetery, Fort Worth.

Chester Katenkamp wrote a series of Office Machine Practice booklets, of which this is the one for the Comptometer. Others include the Burroughs calculator, the Monroe calculator, and the Sundstrand machine. It is essentially a manual and course, explaining the four arithmetic operations an providing practice exercises. It also has sections on handling fractions and decimal points.
This book is in good condition, partly because the centre pages have been strengthened with tape along the spine to prevent the staples from tearing through, and similarly there is tape along the spine on the outside of the cover. There were many pencil marks inside but I was able to mostly erase them.

Apart from books by Felt & Tarrant themselves, there are also books by others such as this one. It is similar to the Business Arithmetic course book above, also opens vertically, but is printed on only one side. It has 54 pages covering 51 lessons, but there are also 4 loose pages inserted at the back covering lesson 117. Note that the book also mentions the Burroughs calculator, a cheaper rival calculator that is very similar to the Comptometer but without the error detection mechanisms.
The front of this course book has been signed with the student's name, Eileen Powell.

This is another course book for both the Comptometer and the Burroughs calculator. It consists of 40 lessons, with an emphasis on addition, but also covers subtraction, multiplication and division. Its pages have perforations, so that when the answers to an exercise are filled in, it can be torn out and handed in to the teacher. This may make this book somewhat rare to find despite having been very widely used as an alternative to Felt & Tarrant's Comptometer Course for Business Training. There were five editions - 1940, 1947, 1952 (shown here), 1959, and 1964.

This is also a course book for both the Comptometer and the Burroughs calculator, and it contains 59 jobs. As with Meehan's book above, its pages are designed to be filled in and torn out as they have perforations near the spine, and this may make it somewhat rare to find this book intact. Shown here is the second edition from 1942, but the 1949 third edition follows below.

This third edition has virtually the same contents as the second edition above, but it is laid out differently because the book is now spiral bound and of a different format. Each page page has a vertical perforation at about one third of the way along. The inner third of the page contains an explanation of a job, and the detachable two-thirds has the job itself with spaces where the answers can be filled in. There was a fourth edition of this book in 1962, and also a sequel, the "Advanced Key-Driven Calculator Course" by Peter Lawrence Agnew and Mary Margaret Brady in 1958.

The Kantoormachine Gids was a Dutch consumer guide to office machines. It gave detailed technical specifications of the many office machines that were available. It was printed on loose perforated pages that could be kept in a ring binder, so that as when new machines appeared on the market, new pages could be added. Presumably you could get a subscription so that you would be sent regular updates.

The 10 pages here consist of:
a 4 page installment from July 1939 describing the models J, JS (Super Totaliser), and K;
2 pages from June 1940 describing the model M;
4 pages from April 1951 describing the 992 and 3D11 models.