We measure the alcohol content of wine with an Ebulliometer which compares the boiling temperature of the wine with the boiling temperature of water at a given atmospheric pressure point.
The procedure is
Step 1: Rinse the boiler / heating chamber: Rinse the cooling tank by pouring some water into the big opening on top, and then fill the boiler by pouring water into the small opening C. Open the tap, incline the instrument to 45 degrees to the front and empty the boiler. Blow out the remaining water in the boiler by blowing into C while obstructing the hole A for the thermometer with a thumb
Step 2: Determine the water boiling temperature: Fill the graduated glass up to the mark “Eau” and pour it into the boiler through the top hole C. Do not put water into the cooling tank! Place the thermometer into its hole A. Light the alcohol lamp and place it under the boiler shaft. After a few minutes steam comes out of the top and the thermometer is steady at the water boiling point. Put that temperature on the sliding wheel directly opposite the zero mark on the fixed part of the calculator
Step 3: Determine the boiling point of the wine. Empty the boiler and rinse it with some wine poured into the to top opening C, fill it completely and then empty it and close the tap. Fill the graduated glass with the wine sample up to mark “vin” and pour it into the boiler. Put the thermometer into its place. Fill the cooling tank with cold water. Light the alcohol lamp and place it under the boiler shaft. After 5 minutes the mercury will rise and then stop; wait 30 seconds then read the temperature. Extinguish the heater flame. Read off the alcohol % directly opposite the boiling temperature of the wine on the moveable disk.
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