Paris pneumatic post
It was established because of the popularity of the electric telegraph in the city which had led to the signal cables becoming overloaded and messages being sent by road.
The pneumatic system allowed the telegraph companies to send messages underground through sealed lines laid in the Paris sewers, bypassing any traffic on the roads above.
Part of this network, connecting the senate, national assembly and officers of the Journal Officiel de la République Française, survived in use until 2004.
[2] As early as 1853 a pneumatic tube message system was installed by Josiah Latimer Clark to link the London Stock Exchange with the offices of the Electric Telegraph Company.
[4][5] In December 1866 the first line of a pneumatic messaging service was installed between the offices of the Central Télégraphique in Rue Feydeau and Le Grand Hotel in Boulevard des Capucines, a distance of 1.05 kilometres (0.65 mi).
The messages were carried in containers within a steel tube of 65 millimetres (2.6 in) diameter, buried 1 metre (3.3 ft) below ground.
[3][6][7] Messages from hotel guests were transported through the 1,060-metre (3,480 ft) long tube to the telegraph office from where they could be transmitted onwards.
A pressure of 2 standard atmospheres (200 kPa) was capable of being generated, which allowed a cylinder 5.5 inches (14 cm) long and carrying 40 messages to be transmitted in 60–80 seconds.
[3][6] This network utilised the same 65 millimetres (2.6 in) tubes of the Grand Hotel line and permitted curves of 5–20 metres (16–66 ft) radius.
[2] The tubes were laid in the Paris sewers, reducing the need for new trenches and allowing ready access for repairs and maintenance.
In addition the cost to the user was not linked to length, except that each message had to be written on pre-franked forms, while telegrams were charged per word.
[3] The pneumatic messages travelled at a speed of around 24 kilometres per hour (15 mph), driven by high and low air pressures provided by eight ateliers de force motrice (motive power workshops) including those at Breteuil, Forest, Valmy, Poliveau, Saint-Sabin, Lauriston and Pajol.
[18] Louis Gaillard, a recent graduate of the École Nationale Supérieure des Télécommunications, was placed in charge of the workshops in 1932.
[6]: 148 [22] The closure followed the introduction of two new services by the ministry: Postéclair, a public fax system, and Postexpress, a rapid parcel delivery network in Paris.
[23] A separate government network of pneumatic lines also existed and connected the Senate, National Assembly and the Journal Officiel de la République Française.
[24] With the advent of fax and email communication the network was gradually dismantled, the dedicated route from the senate and national assembly to the Journal was the last to be decommissioned, being taken out of service in 2004.
