Propolis propolis has approximately 50 constituents, primarily resins and vegetable balsams (50%), waxes (30%), essential oils (10%), and pollen (5%). Propolis also contains persistent lipophilic acaricides, a natural pesticide that deters mite infestations. In neotropical regions, in addition to a large variety of trees, bees may also gather resin from flowers in the genera "Clusia" and "Dalechampia", which are the only known plant genera that produce floral resins to attract pollinators. "Clusia" resin contains polyprenylated benzophenones. In some areas of Chile and Argentina Andean valleys, propolis contains viscidone, a terpene from "Baccharis" shrubs, and in Brazil and Paraguay, naphthoquinone epoxide has
Rabbit-skin glue it. The primary purpose of Rabbit-skin glue is to stretch the canvas. Rabbit skin glue is an animal glue created by prolonged boiling of animal connective tissue. Rabbit skin glue can be bought in powder form or in larger chunks. Preparation involves using the correct proportion of water to glue to achieve the correct consistency and strength. It should be heated to just short of the boiling point. Too much heat results in a product with reduced adhesive qualities. Manufacturers of rabbit, and cow & horse hide glue recommend dissolving at . As an adhesive, Rabbit-skin glue is used in