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The Webb Adder

The Webb Adder

The Webb Adder
Newspaper and Magazine Articles

The Webb Adder

The Webb Adder, or Webb's Adder, is one of the first highly successful adders. It was invented by Charles Henry Webb, who was a poet and writer. The first model of the adder was marketed from 1869, and from 1890 onwards a new redesigned model was sold. From about 1900 other manufacturers sold virtually identical copies of this second model, presumably under licence. Mine must be one of those copies, as it has no brand name, patent number, or serial number anywhere. It may in fact be one that was sold under the "Lightning Calculator" name by The Book-Keeper Publishing Company Ltd., in Detroit, Michigan.

The Webb Adder
The Webb Adder
The Webb Adder
The Webb Adder
The Webb Adder
The Webb Adder
The Webb Adder

The Webb Adder has two number wheels connected by a simple but effective carry mechanism. The large number wheel on the right counts from 00 to 99, while the left wheel counts from 0 to 49, allowing for totals up to 4999.

The right wheel has 100 evenly spaced small holes, and they line up with the numbers 00 to 99 etched into the cover plate. Simply put a stylus in the appropriate hole and turn the wheel clockwise until your stylus hits the small tab at the right, very similar to dialling an old-fashioned rotary telephone dial. The left wheel has only 10 holes exposed (the other 40 are hidden behind the front cover), so any number from 0 to 999 can be added to the total.

To clear the total, find the hole in the large wheel that is marked on the wheel itself with a 0. Some versions have an image of a pointing hand etched in the wheel there. Dialling that hole resets the right wheel to 00. The left wheel has an extra hole set closer to the centre which you can dial in to reset it to 0. On my adder this extra hole is connected up to the outer hole for zero to form a small slot, so that when you dial it the stylus will slide outwards and into the path of the tab. Other versions of the adder have a separate tab for the reset hole.

The Webb Adder
The Webb Adder
The Webb Adder
The Webb Adder
The Webb Adder
The Webb Adder
The Webb Adder
The Webb Adder
The Webb Adder
The Webb Adder

The carry mechanism uses stored energy, so that moving the large wheel from 98 to 99 takes the same amount of effort as moving it from 99 to 00. There is a cam wheel under the large number wheel arranged so that as the wheel turns from 00 to about 30, a latch is pushed outwards against a spring until it catches the next tooth of a gear under the small number wheel. When the large wheel moves from 99 to 00, the cam wheel allows the latch to be released, and the spring pulls it back, turning the small wheel one step.

The adder was invented by Charles Henry Webb, who was a journalist, and humorist. Apart from the adder, he also invented a machine for loading cartridges (patented in 1874, used by Remington) and improvements in extracting precious metals from ore ( US 768,319, GB 1902 24,417).


Here's a video where I demonstrate how the Webb Adder works and show its insides.

Newspaper and Magazine Articles

Here are some articles about Charles Henry Webb (1834-1905).

Sunbeams, the personal announcements section of The Sun
(1869-06-05, The Sun, New York)

1869-06-05 The sun (New York)

No title
(1871-03-17, Sacramento Daily Union)

1871-03-17 Sacramento Daily Union

Charles H. Webb
(1873-10-25, The Cambridge Chronicle)

1873-10-25 Cambridge Chronicle

C. H. Webb, - "John Paul", his self-penned biography entry.
(1873, A Manual of American Literature)

1873 A Manual of American Literature p442
1873 A Manual of American Literature p443
1873 A Manual of American Literature p444

WEBB, Charles Henry, mini-biography.
(1891, Library of American Literature)

1891 Library of American Literature

Charles Henry Webb is dead, Obituary.
(1905-05-25, San Francisco Chronicle)

1905-05-25 San Francisco Chronicle (California)

Charles Henry Webb, Obituary.
(1905-05-28 The Buffalo Times, New York)

1905-05-28 The Buffalo Times (New York)

The Late Charles Henry Webb - "John Paul", Obituary.
(1905-06-04, The New York Times)

1905-06-04 New York Times

In Old Bohemia, part of article in which Webb is described
(1908-03, The Pacific Monthly)

1908-03 Pacific Monthly p261
1908-03 Pacific Monthly p262
1908-03 Pacific Monthly p265

WEBB, Charles Henry, mini-biography.
(1932, Nelson's Encyclopedia)

1932 Nelson's Encyclopedia

(1936, Dictionary of American Biography)

1936 Dictionary of American Biography

Here are some articles about the Webb Adder.

No title, Webb obtains patent
(1868-04-10 The Evening Post, Chicago)

1868-04-10 The Evening Post (Chicago Illinois)

(1869-02-11, The Brooklyn Union, New York)

1869-02-11 The Brooklyn Union (New York)

Adding Machine
(1869-02-25, Leavenworth Daily Commercial, Kansas)

1869-02-25 Leavenworth Daily Commercial (Kansas)

A Snake Fight
(1869-02-25, Sacramento Daily Union)

1869-02-25 Sacramento Daily Union

Webb's Adder
(1869-04-04, The Leavenworth Times, Kansas)

1869-04-04 The Leavenworth Times (Kansas)

Webb's Adder
(1869-04-29, Rutland Weekly Herald, Vermont)

1869-04-29 Rutland Weekly Herald (Vermont)

A Practical Adding-Machine
(1869-07, Bankers Magazine)

1869-07 Bankers Magazine p37
1869-07 Bankers Magazine p38
1869-07 Bankers Magazine p39

No title Gold Exchange Bank
(1869-10-29, The Aegis and Intelligencer, Bel Air, Maryland)

1869-10-29 The Aegis and Intelligencer (Bel Air Maryland)

Personal Intelligence, the society announcements section of The Sun
(1869-11-02, The sun, New York)

1869-11-02 The sun (New York)

Mr Webb's Adder
(1870-08-18, Hawkes Bay Times, New Zealand)

1870-08-18 Hawkes Bay Times (NZ)

American. Additions-Maschine
(1890-12-10, Zeitung fur Landwirthschaft)

1890-12-10 Zeitung fur Landwirthschaft

Webb's Adder
(1892-02, The Compass)

1892-02 The Compass

No title Webb's Adder Company's effects sold off
(1894-02-21 The Sun, New York)

1894-02-21 The Sun (New York)

No titleTrustee buys Webb Adder
(1898-05-13, The Alma Enterprise, Kansas)

1898-05-13 The Alma Enterprise (Kansas)

Seal v. Beach
(1902-04, Federal Reporter)

1902-04 Federal Reporter
1902-04 Federal Reporter
1902-04 Federal Reporter


Here are various advertisements for the Webb Adder, both the first and second model.

1869-01-16 The Sun (New York) 2
1869-01-16 The Sun (New York)
1869-02-13 Harpers Weekly
1869-02-27 Scientific American
1869-06-19 The Daily Standard (Raleigh North Carolina)
1869-06-19 Harpers Weekly
1869-07 American Agriculturist
1869-07-02 The Times Picayune (New Orleans Louisiana)
1869-07-03 Scientific American
1869-07-13 Neosho Valley Eagle (Jacksonville Kansas)
1869-12-11 Harpers Weekly
1890-01 Century Illustrated Monthly Magazine
1891-01 Century Illustrated Monthly Magazine
1891-02-03 The Ottawa Journal (Ontario)
1891-03-18 The Scranton Republican (Pennsylvania)
1891-04-04 Scientific American
1892-07-29 Indianapolis Journal
1901-06-29 Scientific American
1905-07 business man's magazine


PatentFiling datePublish dateNameDescription
US 75,32210-03-186810-03-1868C. H. WebbImprovement in Adding-Machines (Model 1 Webb Adder)
US 414,95928-04-188812-11-1889Charles Henry WebbAdding-Machine (Model 2 Webb Adder)
US 414,33510-07-188905-11-1889Lester C. Smith (assigned to Charles Henry Webb)Adding-Machine (improved carry mechanism for the Model 2 Webb Adder)
US 465,12025-06-188815-12-1891Charles Henry WebbAdding-Machine (Webb's Ribbon Adder)
US 1,263,24427-04-191616-04-1918John L. HerringWebb Adder with adjustable offset


© Copyright 2017 Jaap Scherphuis, .