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The theory of the workshop register

Reading an article of the Abbot Moigno, written in january 1854 in the celebrated scientific journal Cosmos, the theory of the workshop register originated. The author indicates that by that time, over 200 machines of capacity 10 (5x10x0) and around 50 machines of capacity 16 (6x0x16) had emerged from the workshops. If we take the year 1850 as the starting point, this means a little more than 50 machines a year with 10 places, and a good dozen machines with 16 places. It is of course only a statistical mean, but nevertheless interesting.

Why ?

Let's start out from the principle that the head of the workshop would keep a register from the very start, of all the machines that were made (but not necessarily sold, because Thomas, remember, donated a large number of them) (??). They started to make machines with 5 places (5x0x10), then machines with 8 places (8x0x16). Each model had its own numbering. Not surprising, seeing that the same numbers can be found on the faceplate of machines of different capacity, made in different years !

Capacité	Numéro de série	Année
5x0x10	S/n 118	1852
8x0x16	S/n 118	1854

We know that in July 1852, Thomas offered S/n 151 (5x0x10) to his niece Zenoide de Jacquemain. This number fits well with the supposed pace of construction. Indeed, when entering the third year of construction, at a pace of 50 machines a year, one would expect in 1852 machines with S/n between 100 and 150. Perfect ! But what happened to the first serial numbers ?

In fact, Thomas did not start immediately to engrave the machines with their serial number, judging no doubt that it wasn't necessary. But by 1852, everything seems to start up. We find the first publicity flyers, and the first user manuals. So many telltale signs of the first phase of commercialisation.

It is in this period that Thomas perfects a new model (T1852), available in two versions (5x0x10/8x0x16). He decides to have them engraved with their serial numbers, near the inventor's stamp. But although he could have started his numbering from 1, he took instead the numbers from the register. If 100 machines T1850 had been built previously, well then, the numbering would commence at S/n 101 ! Identically so for the machines with 16 places : if 30 had been constructed previously, the numbering would commence at S/n 31.
As a consequence, and following this hypothesis, there should be no machines T1852 with 8 places having numbers below 100, nor machines T1852 of 16 places with numbers below approx. 25.

If, as the Abbot Moigno reminds us in Jan, 1854, only 50 machines of 16 places have been constructed since 1850, the construction speed is now increasing. The arithmometer offered to Mr. Le Verrier, director of the Imperial Observatory in Paris, is the perfect example, since it carries S/n 104, which implies production had doubled over the course of a year. This is not impossible, since 1854 was a splendid year for Thomas, and the abundant literature testifies to that.

Additionally, the inventor probably concentrated simply on the production of machines with 16 places. All machines of that year, in public and private collections in the entire world, have 16 places !!

The political events of 1854-55 (Crim war) intervene with this flamboyant take-off, but doing the sums, we arrive at over 300 machines in 5 years, or approx. 60 machines per year.

The question can be asked why no machines with S/n 200, 300 and even 400 exist. In fact the theory of the register here makes again perfect sense. Between 1856 and 1863, Thomas never stopped improving his machines. Numerous new models appeared out of the workshop. Unfortunately only few have survived, which makes an analysis difficult. Nevertheless, we notice that regardless of capacity and model, they all have serial numbers below 52. Is this to mean that every model had its own numbering ?
- Yes, probably, because it is difficult to believe that in the course of 5-7 years only 60 machines would have been constructed !

In 1865, a new patent is deposited. New machines, new manufacturer's stamp, new numbering ! Thomas has by now a model catalogue which is impressive. There are the models T1860 with revolution counter - 12 and 16 places, that still need to be sold. He also has small models made, not so expensive, without the revolution counters, that resemble the models of 1856 with the "high horizontal" reversing switch. And then there are the new 1865 models available in 3 capacities (12, 16 and 20 places). The inventory of the workshop at 16 rue de la Tour des Dames in 1870 at the death of Thomas de Colmar, shows that all these models were in stock.

Intitulé	Modèle	Nombre	Prix unitaire

Machines de 12 chiffres à quotient ordinaire	T1860 A	40	100 fr.
Machines de 16 chiffres à quotient ordinaire	T1860 B	33	150 fr.
Machines de 10 chiffres sans quotient (5x0x10)	T1865 -	13	50 fr.
Machines de 12 chiffres à quotient effaceur	T1865 A	58	200 fr.
Machines de 16 chiffres à quotient effaceur	T1865 B	76	250 fr.
Machines de 20 chiffres à quotient effaceur	T1865 C	9	400 fr.

Let's revisit the numbering scheme now ...

Thomas lets the new series begin at S/n 500. Logically, this leap to 500 is nothing out of the ordinary if we follow the hypothesis of the workshop register : the number of machines built since 1850 must be close to 500. If it were decided to use hanceforth a unique numbering scheme, regardless of the type and model of the machine, then let it start at 500 !