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Portable / Corona Adding Machine

Portable Adding Machine

Portable Adding Machine

Portable Adding Machine

The Portable Adding Machine is a simple and compact adding listing machine from the mid-1920s. It has a full keyboard with 7 columns. If you enter a number on the keyboard and pull the large lever, the number is printed and gets added to the internal register, and the keyboard input is cleared automatically. There are 4 further controls. The switch lever at the far left has two functions - when pulled forward (marked Error) it clears the keyboard, and when pushed back (marked Repeat) it will not clear the keyboard automatically after every addition to allow repeated addition of the same number. At the back right is the Total button, which can be held down with the thumb as you begin to pull the lever, and that will print the current subtotal. This button is disabled if the last addition involved carries, in which case an extra pull of the lever is needed before the total can be printed. At the front right is the Non-Print button which can be locked down to disable the printing during the next addition. The button at the middle right (marked C or Clear) can be locked in the down position, and serves two functions - instead of an addition it will just print the number without adding it, and instead of a subtotal it will print the total, i.e. also clear the register. The button automatically unlocks after the lever is pulled.

Portable Adding Machine
Portable Adding Machine
Portable Adding Machine
Portable Adding Machine
Portable Adding Machine
Portable Adding Machine
Portable Adding Machine
Portable Adding Machine
Portable Adding Machine
Portable Adding Machine
Portable Adding Machine
Portable Adding Machine

I have not found any serial number on the machine. It was made in 1924 or 1925, since it is not yet named the Corona.

The machine is very cleverly designed to be as simple as possible, which allowed it to be relatively cheap ($65 in 1924, which is equivalent to about $1150 today). The printing is done by moving the paper forward against the type. The ink ribbon reels are mounted together on the left side of the case, with a simple and compact advancing mechanism that is triggered by the movement of the paper. Another simplification is that there is no mechanism to deal with zeroes - you need to enter any zeroes in a number or else they will not be printed, and when totals are printed they will have leading zeroes. Using the Non-Add/Clear button causes a little dash to be printed after the number, so this simple combined mechanism allows you to distinguish subtotals from totals, and additions from non-additions.

This adding machine was in pretty good condition when I found it at a large antiques market. I just had to find replacements for two springs that were missing from the ink ribbon mechanism, give it a clean and replace the ribbon and add paper.

Portable Adding Machine
Portable Adding Machine
Portable Adding Machine
Portable Adding Machine
Portable Adding Machine
Portable Adding Machine
Portable Adding Machine
Portable Adding Machine
Portable Adding Machine
Portable Adding Machine
Portable Adding Machine
Portable Adding Machine
Portable Adding Machine
Portable Adding Machine
Portable Adding Machine
Portable Adding Machine
Portable Adding Machine
Portable Adding Machine
Portable Adding Machine
Portable Adding Machine
Portable Adding Machine
Portable Adding Machine
Portable Adding Machine
Portable Adding Machine
Portable Adding Machine
Portable Adding Machine



The Portable was designed by Glenn J. Barrett. At first he designed typewriters, working for Fox Typewriter Company in Grand Rapids, and then in 1904 he set up the Barrett Typewriter Company to produce his own typewriter. He then left typewriters behind and designed an adding machine, and in 1910 set up the Barrett Adding Machine Company to produce them. He left that company about 5 or 6 years later to become a consultant to other adding machine companies such as Burroughs. In about 1923 he designed the Portable adding machine and set up the Portable Adding Machine Company to market it. That company contracted out the manufacturing to the Corona Typewriter Company, a reputable typewriter manufacturer.

The Corona Typewriter Company began in 1906 as the Rose Typewriter Company, and made the first successful portable typewriter. in 1909 they were bought by the L.C. Smith & Bros. Typewriter Company and renamed the Standard Typewriter Company. The model Corona portable typewriter became very successful, and led to yet another name change in 1914 to the Corona Typewriter Company. Finally, in 1926 Corona and the parent company L.C. Smith & Bros. were reorganised to become L.C. Smith & Corona Typewriters Inc.

The Portable Adding Machine Company's ties to Corona became ever closer. In August 1925 the Portable adding machine was renamed the Corona adding machine. The company moved to Syracuse NY in 1928, to where Smith & Corona were based, and officially became a division of the latter. From 1931 all sales of the Corona adding machine were done through the Smith-Corona dealerships, which essentially meant the end for the Portable Adding Machine Company. Glenn J. Barrett officially retired in 1934, but still continued to develop his machine, even resulting in a further patent. In 1958 Smith-Corona bought Marchant and became Smith-Corona-Marchant (SCM). While they did move into electronic desk calculators, they could not compete against electronic pocket calculators, so stopped making calculators in the early 1970s.


The Portable/Corona adding machine was continuously improved and developed, so versions of the machine were in production from late 1923 until the 1960s. It is difficult to find out information about all the variant models. In the advertisements the models are often given simpler names/numbers that do not match the list of model designations found in official records. In the table below I have gathered observations from ads and articles.

1923-08Portable Adding Machine announced. It cost $65, had 7×7 capacity, a single (Sub)Total button, full keyboard with small keys and including zeros, black cast metal case. It took about a year till mass production was underway.
1925-08Renamed to Corona Adding Machine. Now has separate Total and Subtotal buttons, larger key tops and red buttons instead of zeroes.
1926-07Corona Cash Register announced. This combines the Corona adding machine with an Indiana cash drawer and Hanna register. The left key column of the adding machine is used for marking the type of transaction.
1927-09Corona Accounting Cashier is the updated version of the cash register. It has a new case that encloses the printing mechanism.
1928-05Corona 10 produced. It has 9×10 capacity, larger key tops with complementary digits, a subtract button in place of the non-print button, and the closed case of the cash register. The standard adding machine is unchanged and now called the Corona 7.
1928-12Corona 9 produced. It like the Corona 7 but with 9×10 capacity. No Non-Print button, but Non-Print lever on the printing mechanism.
1929-07Corona 7 redesigned. Larger keytops, Non-Print lever instead of button.
1940-07Model 6K has 5×6 capacity. Probably in production since about 1933.
1946-09Models 8M to replace the 8K. Closed grey case with window, with paper ejector button.
1949-08Case restyled in grey-brown, with a larger window, and green keys ("colorspeed" keyboard).
1956-08Case restyled in light grey, without a window, larger totals buttons, white/brown keys.
1960-03Case restyled in white grey or beige, handle and keys of the same colour set against a black keyboard plate. Subtracted numbers printed in red (on models with subtraction).


1923-08 Office Appliances 1
1924 The American Digest Of Business Machines 2
1924-10 Office Appliances
1925 Ernst Martin
1925-09 Office Appliances 1
1926-05 Office Appliances 1
1926-07 Office Appliances
1927-01 Office Appliances
1927-09 Office Appliances
1927-11 Office Appliances 1
1928-02 Office Appliances 2
1928-05 Office Appliances
1929-08 Office Appliances
1930 Organisations-Lexikon
1931-05 Office Appliances
1937 The American School and University
1938-07 Modern Plastics
1938-07 Office Appliances
1938-10 Modern Plastics
1940-10 Office Appliances
1946-09 Office Appliances
1950-05 Modern Plastics
1954-08 Administrative Management
1960-09 Plastics Technology

Fortune, August 1944: A Dream of Reconversion

1944-08 Fortune 1
1944-08 Fortune 2
1944-08 Fortune 3
1944-08 Fortune 4
1944-08 Fortune 5
1944-08 Fortune 6
1944-08 Fortune 7
1944-08 Fortune 8


1923-1925 Portable

1923-08 Office Appliances 2
1923-09 Office Appliances
1923-10 Office Appliances
1924 The American Digest Of Business Machines 1
1924-01 Office Appliances
1924-10 Office Appliances 2
1924-11 Office Appliances
1925-01 Office Appliances
1925-02-02 Rushville Daily Republican
1925-02-24 Chicago Tribune
1925-04-09 Chicago Daily Tribune
1925-06-30 Chicago Daily Tribune
1925-10-07 Hong Kong Telegraph

1925-1961 Corona

1925-09 Office Appliances 2
1925-10 Office Appliances
1925-10 Scientific American
1925-10-10 Saturday Evening Post
1925-10-12 Time
1925-11 Office Appliances
1926-04-13 Chicago Daily Tribune
1926-04-20 Chicago Daily Tribune
1926-05 Office Appliances 2
1926-07-17 Gettysburg Times
1926-08 Office Appliances
1926-10 Office Appliances
1927-09 Office Appliances 2
1927-10 Office Appliances
1927-11 Office Appliances 2
1927-12 Office Appliances
1928-01 Office Appliances
1928-02 Office Appliances
1928-04 Office Appliances
1928-04-25 National Petroleum News
1928-05 Office Appliances 2
1928-07 Office Appliances
1928-08 Office Appliances 2
1928-08 Office Appliances
1928-10 Office Appliances
1928-11 Office Appliances
1928-12 Office Appliances
1929-01-05 Hufvudstadsbladet
1929-02 Office Appliances
1929-03 Office Appliances
1929-04 Office Appliances
1929-05 Office Appliances
1929-06 Office Appliances
1929-07 Office Appliances
1929-09 Office Appliances
1929-10 Office Appliances
1929-11 Office Appliances
1929-12 Office Appliances
1930-05 Office Appliances
1938-06-09 Mansfield News Journal
1940-07 Office Appliances
1947-05-10 The Saturday Evening Post
1949-08 Office Appliances
1949-10 Business Education World
1950-02 Farm Journal
1950-11 American Builder
1950-12 Nation's Business
1951-02 The Kiwanis Magazine
1951-04 American Builder
1951-04 The Rotarian
1951-05 The Kiwanis Magazine
1951-07 Office Appliances
1951-09 Nation's Business
1951-10 The Kiwanis Magazine
1951-11 American Builder
1951-11 Nation's Business
1952-02 Chilton's Motor Age
1952-03 American Builder
1952-05 American Builder
1952-09 Nation's Business
1952-09 Office Appliances
1952-10-08 Pathfinder
1952-11-19 Pathfinder
1952-12 Office Appliances
1953-02 Nation's Business
1953-04 Office Appliances
1953-05 The Rotarian
1953-10 Nation's Business
1954-04 Nation's Business
1955-06 Farmers' Federation News
1955-06 Nation's Business
1955-06-04 The Saturday Evening Post
1955-09 Office Appliances
1955-10-01 The Saturday Evening Post
1956-01 Office Appliances
1956-09-29 The Saturday Evening Post
1956-10 Nation's Business
1956-12 Nation's Business
1957-03 Nation's Business
1957-04 Office Appliances
1957-10 Office Appliances
1957-11 Nation's Business
1958-09 The Rotarian
1959-12 Nation's Business
1960 W. Bell & Co. Department Store
1960-03 Office Appliances
1960-05 Nation's Business
1961-02 Office Products
1961-10-27 Time
1961-62 The Farm Quarterly


PatentFiling datePublish dateNameDescription
US 1,681,56707-05-192321-08-1928Glenn J. Barrett; Portable Adding Machine CompanyAccumulator-control means
US 1,734,06931-08-192705-11-1929Glenn J. Barrett; Portable Adding Machine CompanyListing mechanism
US 1,743,26124-12-192814-01-1930Glenn J. Barrett; Portable Adding Machine CompanyLocking device for case
US 1,784,86214-08-192516-12-1930Glenn J. Barrett; Portable Adding Machine CompanyKeyboard module
US 1,788,37614-08-192513-01-1931Glenn J. Barrett; Portable Adding Machine CompanyRibbon feeding mechanism
US 1,804,73624-12-192812-05-1931Glenn J. Barrett; Portable Adding Machine CompanyPaper feeding mechanism
US 1,811,84014-08-192530-06-1931Glenn J. Barrett; Portable Adding Machine CompanyAdding listing machine
US 1,812,12907-10-192730-06-1931Glenn J. Barrett; Portable Adding Machine CompanyCalculating mechanism
US 1,812,13014-08-192530-06-1931Glenn J. Barrett; Portable Adding Machine CompanyAdding listing machine
US 1,812,16115-07-192630-06-1931Clarence Orin Mapel; Portable Adding Machine CompanyPrinting mechanism
US 1,829,72722-10-192703-11-1931Glenn J. Barrett; Portable Adding Machine CompanyPaper rewind
US 1,906,30423-10-193102-05-1933Glenn J. Barrett; Portable Adding Machine CompanyPrinting mechanism
US 1,925,08908-09-193105-09-1933Glenn J. Barrett; Portable Adding Machine CompanyTotalling device
US 1,935,60917-06-193121-11-1933Glenn J. Barrett; Portable Adding Machine CompanyTotal key unlocking means
US 1,947,51208-09-193120-02-1934Glenn J. Barrett; Portable Adding Machine CompanyAutomatic signal
US 1,949,44511-04-193206-03-1934Glenn J. Barrett; Portable Adding Machine CompanyNon-add key latching mechanism
US 1,949,44606-10-193206-03-1934Glenn J. Barrett; Charles H. Bradt; Portable Adding Machine CompanyAdding listing machine
US 1,949,70625-04-193206-03-1934Glenn J. Barrett; Portable Adding Machine CompanyPrinted clear indication
US 1,951,59227-04-193120-03-1934Glenn J. Barrett; Portable Adding Machine CompanyZero suppression
US 2,199,25306-05-193830-04-1940Glenn J. Barrett; L.C. Smith &Corona Typewriters Inc.Carry mechanism
US 2,218,10816-01-193915-10-1940Edwin L. Harmon; L.C. Smith &Corona Typewriters Inc.Paper feed mechanism
US 2,281,74202-11-193905-05-1942Charles H. Bradt; L.C. Smith &Corona Typewriters Inc.Key column for item type
US 2,539,90622-04-194730-01-1951William J. Higgins; L.C. Smith &Corona Typewriters Inc.Full stroke mechanism


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