Barograph Recording Instrument - Brass & Mahogany - Solid Top w/HandleMechanical barographs have a solid rotating brass drum that is driven by a quartz battery movement to rotate the drum once a week. A felt tip pen at the end of the of the writing arm shows changes in the air pressure on a paper diagram that is wrapped around the drum. A mechanical barometer movement with four round diaphragms measures variation in the air pressure and transfers it very precisely through a system of mechanical levers to the writing arm. All barographs come with a supply of charts and felt tip pens for one year.Functions:Barograph:Graphical Display of Air PressureTechnical Data:Precision Barograph4 DiaphragmsQuartz Movement for Diagram drum52 x 1 Week Diagram paperMeasure: H5,5cm x L23,5cmResolution: 2hPaEffectiveness 960…1050hPaLinearity deviation +-2hPa between980..1040hPaQuartz Movement, Power supply:1 x LR6 1,5V AA (Mignon Battery)Frame / Dial:MahoganyDimension frame: 195 x 125 x 127mmWeight: 1.360gPackaging:Measure Gift Box27,5 x 19,9 x 20,7cmWeight incl. Instrument 1.640g