The derivation of 40° vodka formula was really an interesting story. It was the time world over running researches on weight analysis on alcoholic solutions. Mendeleev received the accurate results by missing the alcohol with water-based on weights while the whole other world used to mix by volumes. Then he formulated as the precise content of spirit in vodka to be 40°. Upon reciprocal dilution the largest compression a mixture can be made. That is 45.88% of anhydrous spirit can be mixed with 54.12% of water. To explain this exactly 1 litre of 40° vodka weights 951 grams exactly (Allaby & Gjertsen, 2002).