About Serial Numbers and Machine Models
The following information contained in quotations, is from The American Digest of Business Machines (1924), describing the Burroughs approach for identifying their machine models.
Classes and Models:
Early machines were designated in "Classes" with a sub-designation of "Styles" or 'Models". Each Class of machine was identified with a single number, such as Class 1, Class 2, etc. Within the class of each machine type, there were a variety of styles or models. Style designations were usually a numeric and sometimes alpha characters, such as Style 6 or Style 6x. These type of designations continued for many years, until about 1952, when the "Series" designation was introduced. The Series designations were alpha characters, such as Series P. So a Class 8 machine would, in later production, become a Series P machine.
"Serial Numbers:
The serial number is stamped on the front of the base of every machine. It should be noted that the serial numbers of all early models are comparatively low - in all cases less than 260,000."
"Until 1914-1915, machines were not numbered in sequence. The practice was to reserve a series of 1,000 to 5,000 numbers (more or less), and assign them to one style or model, and when that series was exhausted, a new set, in a different series, would be assigned. Thus, a model will have serial number groups of serials, sometimes in the same year of manufacture. The intervening numbers were assigned to other models."
In about 1934, Burroughs serial numbers had reached seven digits long. It must have been obvious that it was becoming difficult to handle these large numbers. So the serial numbers started over again from number 1 with the alpha "A" proceeding the number. This continued for all current products until abut 1950, when the "A" was changed to "B". Then in 1952, they started over again with the Series identification alpha character in front of the actual number. As you may start to see, you can identify the period a machine was built by the serial number alpha character. An example is as follows:
Class 8 Portable Adding Machine serials would be as follows:
8-123456 (1925 - 1934)
A123456 (1934 - 1950)
B123456 (1950 - 1952)
P123456 (1952 -
"Dates of Manufacture:
When the above plan of numbering was abandoned, a regular sequence was maintained; each machine , regardless of its class or model, was assigned a consecutive factory number. The following table is an approximation of such serial numbers. The necessity of maintaining sale and consignment stocks of various models, often brings about a condition whereby a machine is not sold for many months after its manufacture. Thus it sometimes develops that, judged by actual date of sale, the following table will not appear correct. The dates shown below are believed to be the approximate dates of manufacture."
"Serial Date Serial Date Serial Date
260,000. . . . . . . Jan., 1915 450,000. . . . . . .Aug., 1918 700,000. . . . . . Dec., 1920
280,000. . . . . . . Oct., 1915 500,000. . . . . . .May., 1919 750,000. . . . . . .Jan., 1922
300,000. . . . . . . May., 1916 550,000. . . . . . .Feb., 1920 800,000. . . . . . .Jan., 1923
350,000. . . . . . . Feb., 1917 600,000. . . . . . .May., 1920 820,000. . . . . . .Jan., 1925"
400,000. . . . . . .Nov., 1917 650,000. . . . . . .Aug., 1920
Classes and Models:
Early machines were designated in "Classes" with a sub-designation of "Styles" or 'Models". Each Class of machine was identified with a single number, such as Class 1, Class 2, etc. Within the class of each machine type, there were a variety of styles or models. Style designations were usually a numeric and sometimes alpha characters, such as Style 6 or Style 6x. These type of designations continued for many years, until about 1952, when the "Series" designation was introduced. The Series designations were alpha characters, such as Series P. So a Class 8 machine would, in later production, become a Series P machine.
"Serial Numbers:
The serial number is stamped on the front of the base of every machine. It should be noted that the serial numbers of all early models are comparatively low - in all cases less than 260,000."
"Until 1914-1915, machines were not numbered in sequence. The practice was to reserve a series of 1,000 to 5,000 numbers (more or less), and assign them to one style or model, and when that series was exhausted, a new set, in a different series, would be assigned. Thus, a model will have serial number groups of serials, sometimes in the same year of manufacture. The intervening numbers were assigned to other models."
In about 1934, Burroughs serial numbers had reached seven digits long. It must have been obvious that it was becoming difficult to handle these large numbers. So the serial numbers started over again from number 1 with the alpha "A" proceeding the number. This continued for all current products until abut 1950, when the "A" was changed to "B". Then in 1952, they started over again with the Series identification alpha character in front of the actual number. As you may start to see, you can identify the period a machine was built by the serial number alpha character. An example is as follows:
Class 8 Portable Adding Machine serials would be as follows:
8-123456 (1925 - 1934)
A123456 (1934 - 1950)
B123456 (1950 - 1952)
P123456 (1952 -
"Dates of Manufacture:
When the above plan of numbering was abandoned, a regular sequence was maintained; each machine , regardless of its class or model, was assigned a consecutive factory number. The following table is an approximation of such serial numbers. The necessity of maintaining sale and consignment stocks of various models, often brings about a condition whereby a machine is not sold for many months after its manufacture. Thus it sometimes develops that, judged by actual date of sale, the following table will not appear correct. The dates shown below are believed to be the approximate dates of manufacture."
"Serial Date Serial Date Serial Date
260,000. . . . . . . Jan., 1915 450,000. . . . . . .Aug., 1918 700,000. . . . . . Dec., 1920
280,000. . . . . . . Oct., 1915 500,000. . . . . . .May., 1919 750,000. . . . . . .Jan., 1922
300,000. . . . . . . May., 1916 550,000. . . . . . .Feb., 1920 800,000. . . . . . .Jan., 1923
350,000. . . . . . . Feb., 1917 600,000. . . . . . .May., 1920 820,000. . . . . . .Jan., 1925"
400,000. . . . . . .Nov., 1917 650,000. . . . . . .Aug., 1920