Low low pressure
I have a barograph (recording barometer) that sits quietly in the corner doing next to nothing.
I save myself the cost of pens and charts by adjusting the mechanism so the pen indicates correctly, but does not touch the chart paper. This can’t be done simply by discarding the pen, since this acts to balance the pen arm, and forms the last few millimetres of its length, so losing it would cause an error in the reading. Even so, I save myself the cost of charts by printing them via a laser printer. This also let me extend the chart area, as the original print had a huge border around the edge of the paper, losing about 10 mb at each end.
I’ve seen low readings before, and the instrument only goes down to 960 mb, but I can’t remember seeing the pen bouncing off the lower end of the scale as seen in the pic below, which has been the normal view for a view days now.
I’ve got some mercury barometers, and fired one up to get a current reading when I took the pic, and that showed our local reading to be 955 mb. I don’t know if it’s been lower, or might get lower, as it’s too much hassle to get regular reading off the mercury barometer. Which was why I slightly re-organised the recording version to indicate without recording.
(Please excuse the dust and fluff – the barometer usually sits safely out of the way on a shelf, where it can’t be bumped or disturbed – or dusted.)
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