Le Parfait régulateur. Ouvrage méthodique, pour apprendre à trouver les rapports entre les mesures anciennes et nouvelles dans une seule leçon

A very rare first edition printed on blue paper (only four copies recorded in the CCFr: Aix-en-Provence (2), Angers and Avignon).

Not recorded in Monglond.

Contemporary flexible boards covered in blue marbled paper, speckled edges.

A few scuffs to the covers, spine restored.

With an additional pierced copper plate indicating units and fractions.

The author, a clerk in the Imperial Navy at Toulon, here sets out, in tabular form, a method enabling the rapid conversion of former units of measurement into the metric system, instituted in 1795 but still little used at the time.

The accompanying copper plate bears the engraved inscription: "Le régulateur fixe toujours d'une manière précise la valeur des nombres qu'il compare", followed by "Invention du Sieur Martin Commis de Marine retraité".

Provenance: bookplate of the American engineer Erwin Tomash (1921-2012), a specialist in computing, pasted at the foot of the verso of the upper cover.