Mash elderberries well in a large (5 gal) pot. Add water. Bring to a boil and simmer for 15 minutes. Slowly stir in sugar and lemon juice. After 15 more minutes at simmer, remove from heat and allow to cool enough to handle. Strain through collander, then through tea strainer, then through cloth into large container, a crock or plastic/glass water container. In a cup of LUKEWARM water dissolve the yeast. Pour into berries and cover well with cloth. Allow to ferment for 10 days. Next, carefully, so as to leave dregs on bottom, pour fermenting juice into gal. jugs. Cork tightly, store in cool, dark 3 months. Draw the wine from the sediment after 3 mos. No aging req'd.