CH 12

CH 12 of Swiss patents in this period was for Ventilation, chauffage et séchage; distribution d'eau; installations pour chauffer l'eau et pour bains; fosses et leiux d'aisances, tuyauterie, tuyaux divers, etc.

References

This wiki has 2 patents in category "CH 12".

Patents in category CH 12

• Patent CH-1891-3995 (English title: Ventilation device, Inventors: August Riedinger, Filing date: 1891-07-20)
• Patent CH-1891-4109 (English title: Single-acting valve machine for pressure gases and vapors, Inventors: August Riedinger, Filing date: 1891-08-07)

Enclosing categories	Swiss patent classifications, 1890-1907
Subcategories
Keywords
Start year	1890
End year	1907