Step #1 Beat egg yolks; add lemon juice, rind & 1/2 c sugar & cook in a double boiler until it thickens.
Step #2 Dissolve the lemon gelatin in 1/2 c hot water or soften the granulated gelatin in 1/4 c cold water for five mins, then dissolve in 1/4 c boiling water.
Step #3 Add dissolved gelatin to first mixture as soon as it has cooked until thickened.
Step #4 ; mix well & cool until it begins to congeal.
Step #5 Lightly butter an 8" square pan & coat bottom & sides with vanilla wafer crumbs.
Step #6 Beat with an whisk.
Step #7 Whip the cream until soft peaks form.
Step #8 Beat egg whites until frothy & add in the remaining 1/2 c sugar a tbsp at a time, beating well between additions.
Step #9 Fold carefully into gelatin mixture along with the whipped cream.
Step #10 Pour into prepared pan & cover with a light sprinkling of the crumbs.