An instrument used to measure Stormy Rain Change Fair and Very Dry. Made in Western Germany. May have been used for boaters.?

Answer 1

Disregard the words Stormy, Rain, Change, Fair and Dry as these are only
traditional zones on a barometer dial. Your barometer indicating hand will
never move all the way to Rain to predict rain or to Stormy to predict
inclement weather. The normal operating range of movement for your barometer
indicating hand is from 1000 to 1030 hPa. Your most extreme readings would
occur before a hurricane or tornado when barometers have dropped as low as
970 hPa (28,5 inches of Mercury); or, at the other extreme if very fair, dry
weather is to come, your barometer may rise to 1050 hPa (30,9 inches of
mercury). The following procedure, if done every 12 hours, or morning and
evening, should give you the best results.
1. Tap the instrument lightly to release any latent action.
2. Adjust set hand directly over the indicating hand. This is your momentary
reading. At a later period you will be able to notice in what direction the
indicating hand has moved since the last setting.
If it moves to the right you have a rising barometer which usually means a
change for the better or continued good weather. If the reading is to the
left you have a falling barometer, which usually means a change for the worse.
A steady barometer means no change. For accurate weather predictions, it is
highly important that your barometer be adjusted to sea level. The correct
sea level reading can be obtained from your Weather Bureau or television
weather forecasts. Readings obtained from your barometer indicate weather
conditions that may prevail within the next 24 to 48 hours, providing wind
direction and velocity remain the same as when readings were obtained.