The Daguin technical canceller produces duplex cancels which are 28 mm center to center. It was invented by the French Eugene Daguin (1849-1888), and was used by various countries. France, Belgium, Italy, Romania, Bulgaria, and Chile are some of them. Each country used different duplex cancels. Bulgaria used a duplex where one part was a datestamp and the other part was the star.

The device was used for the first time in August 1882. But it is only from September 1884 that we find postal marks made with this device in the mail. In 1885 close to 570 machines were installed in France. They were more economic than the electric machines (they only cost 110 French Francs of the time) but were less effective because they had to be operated by hand. Typically 3000 letters could be cancelled per hour. After 1900, the Daguin machine was abandoned to the advantage of the electric machines. In 1923 the appearance of the advertising slogans confered a second youth (Daguin slogans), and some post offices used them for 70 years. In 1984 at the time of the centenary of the machine, several post offices used the machine to cancel the mail.

More info can be found at: http://www.chez.com/memorial/daguin.html (in French)