Self-made simple ink bottle rain gauge

The change of weather is closely related to the change of atmospheric pressure. Under normal circumstances, when the air pressure is stable and slowly rising, it means that the weather will clear up. On the contrary, if the air pressure continues to drop, it means that the weather will turn from sunny to rainy. So we made a simple barometer ourselves, which can predict the change of sunny and rainy weather, so we call this instrument sunny and rainy. 1) Take an ink bottle (other bottles are also acceptable), a 20 cm long thin glass tube, a piece of cardboard or board, a cork (used to plug the glass bottle), a little cooking oil and two good quality rubber bands.

2) Use fine sandpaper to grind the fracture at both ends of the glass tube, or use a small steel chisel to smooth the fracture. In order to prevent cutting your fingers.

3) Drop a drop of cooking oil into the glass tube, then insert the glass tube into the cork, and then insert the cork tightly into the ink bottle.

4) Draw a scale of 14cm on a piece of white paper. The scale can be drawn according to the scale on a ruler or triangle (including centimeter and millimeter lines). Stick the marked white paper on cardboard or cardboard.

5) The rubber band is wound around the two ends of the thin glass tube and then fixed on the board or cardboard card, thus making the rain gauge. L barometer should be placed in a place with stable temperature (such as basement). Otherwise, the change of temperature will affect the change of air pressure and make the observation inaccurate.

2. In order to reduce the influence of heat expansion and cold contraction of the air in the ink bottle, you can add a proper amount of water in the bottle first, so that only a small amount of air remains in the bottle.

3. The cork should be sealed with the glass tube and the ink bottle mouth, and there should be no air leakage. It can be sealed with wax or paraffin wax, or we can melt the candles we usually use for lighting and drop them where it needs to be sealed.

4. You can repeatedly observe the changes of weather and rain gauge, and make records when necessary.