Take two small plastic bags.. fill one with 1 level table spoon of salt (which weighs about an ounce)..
Fill another one with dried lemon peel..
Tie 1 bag to each end of a wooden dowel or something (racking cane or filling wand?) to create a balance (a crude scale), you can even use your finger as the pivot point in the middle...
Add or remove lemon peel until they balance out :-)